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EC 110 ELECTRONICS ENGINEERING WORKSHOP

Electronics engineering workshop

MCET Pathanamthitta

LIST OF EXPERIMENTS

1. Familiarization of electronic components

3. Familiarization of testing instruments and commonly used tools

4. Testing of electronic components

5. Interconnection method and soldering practice

6. Printed circuit board

7. Assembling of electronic circuit/system on general purpose pcb test and show the

functioning

8. Familiarization of Electronic Systems


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EXPERIMENT NO:1

FAMILIARISATION OF ELECTRONIC COMPONENTS

AIM

To familiarize with various Electronic Components such as;

Passive Components

Active Components

THEORY

PASSIVECOMPONENTS

The electronic components which are not capable of amplifying or processing an

electrical signal are called passive components such as resistors, capacitors & inductors.

However, in electronic circuits, these components are important as active components

because without the aid of these components, the active devices cannot process the

electrical signals.

RESISTORS

Resistors are the most commonly used of all electronic components, to the point

where they are almost taken for granted.There are many different resistor types available

with their principal job being to "resist" the flow of current through an electrical circuit, or

to act as voltage droppers or voltage dividers. When used in DC circuits the voltage drop

produced is measured across their terminals as the circuit current flows through them

while in AC circuits the voltage and current are both in-phase producing 0o phase shift.

Resistors produce a voltage drop across themselves when an electrical current flows

through them because they obey Ohm‘s Law, and different values of resistance produces

different values of current or voltage.

There are many types of resistors and they are classified based on their particular

characteristics and accuracy suiting certain areas of application, such as High Stability,

High Voltage, High Current etc, or are used as general purpose resistors where their

characteristics are less of a problem. Some of the common characteristics associated with

the humble resistor are; Temperature Coefficient, Voltage Coefficient, Noise, Frequency

Response, Power as well as Temperature Rating, Physical Size and Reliability.

The unit of resistance, R is ohm and denoted by the Greek symbol ‗Ω‘ (omega).

The schematic symbol of R is shown below;


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Carbon Composition Resistors

Carbon Composition Resistors are the cheap general

purpose resistors. Their resistive element is manufactured

from a mixture of finely ground carbon dust or graphite

(similar to pencil lead) and a non-conducting ceramic (clay)

powder to bind it all together. The ratio of carbon to ceramic

determines the overall resistive value of the mixture and the

higher this ratio is the lower the resistance. The mixture is

then moulded into a cylindrical shape and metal wires or

leads are attached to each end to provide the electrical

connection before being coated with an outer insulating

material and colour coded markings.

CarbonComposite Resistors are low to medium power resistors with low

inductance which makes them ideal for high frequency applications but they suffer from

drawbacks like low stability, more noisy & high temperature co-efficient.

Typical Specifications:

o Available Range : 1Ω to 10MΩ

o Tolerance Range : ±5% to ±20%

o Wattage Range : 0.125 W to 2 W

o Operating temperature : -55°C to 100°C

o DC working voltage : up to 350V

Film Resistors

The category of "Film Resistor" consist of Metal Film, Carbon Film and Metal

Oxide Film resistor types, which are generally made by depositing pure metals, such as

nickel, or an oxide film, such as tin-oxide, onto an insulating ceramic rod or substrate. The

resistive value of the resistor is controlled by increasing the desired thickness of the film


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and then by laser cutting a spiral helix groove type pattern into this film. This has the

effect of increasing the conductive or resistive path. This method of manufacturing allows

for much closer tolerance resistors (1% or less) as compared to the simpler carbon

composition types.

Metal Film Resistors have much better temperature stability than their carbon

equivalents, lower noise and are generally better for high frequency or radio frequency

applications. Metal Oxide Resistors have better, high surge current capability with a much

higher temperature rating than the equivalent metal film resistors.

Another type of film resistor commonly known as a Thick Film Resistor is

manufactured by depositing a much thicker conductive paste of CERamic and METal,

called Cermet, onto an alumina ceramic substrate. Cermet resistors have similar properties

of metal film resistors and are generally used for making small surface mount chip type

resistors, multi-resistor networks in one package for PCB's and high frequency resistors.

They have good temperature stability, low noise, and good voltage ratings but low surge

current properties.


o Available Range : 10Ω to 10MΩ

o Tolerance Range : ±5%

o Wattage Range : 0.25 W to 5 W



1.1.3 Wire-wound Resistors

Wire-wound Resistors are made by winding a thin metal alloy wire (Nichrome) or

similar wire onto an insulating ceramic former in the form of a spiral helix similar to the

film resistors. These types of resistors are generally only available in very low ohmic high

precision values due to the gauge of the wire and number of turns possible on the former

making them ideal for use in measuring circuits and Whetstone bridge type applications.

They are also able to handle much higher electrical currents than other resistors of

the same ohmic value with power ratings in excess of 300 Watts. These high power

resistors are moulded or pressed into an aluminium heat sink body with fins attached to

increase their overall surface area to promote heat loss. The drawback of this type of


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resistor is that they are larger in size; cost‘s high and exhibits poor performance at high

frequencies.


o Available Range : 0.1Ω to 200KΩ

o Tolerance Range : ±5%

o Wattage Range : 3 W to 50 W



1.1.4 Variable Resistors

They are usually used in electronic circuits to adjust values of currents & voltages.

Potentiometers, presets and rheostats are examples of variable resistors.

1.1.4.1 Rheostat

These are usually used in high power applications. It is constructed by winding a

former with a Nickel-Copper wire in oxidation form. Former is usually 15cm – 30cm

long, round

shaped, made of ceramic & coated with vitreous enamel. A movable contact can be

slided through an iron rod. Threading type terminals are provided for external

connections.

Potentiometer

Another type of variable resistor commonly used is

Potentiometers. They are available in the following ranges; 1K,

2.2K, 4.7K, 10K, 22K, 47K, 100K. Power rating of carbon track

potentiometer ranges up to 2W. For

high power applications wire wound potentiometers are used.

Presets

These types of variable resistors are used where the variation of

resistance is not done frequently. Once the setting is made, it may be

undisturbed. These types of resistors have a metallic wiper that can be

moved with a screw driver. The tracks on which the wiper moves are

carbonized or metalized ceramic.


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Capacitors

A Capacitor is referred to as a condenser or a device one which stores energy in

the form of an electrostatic field which produces a potential across its plates. Basically a

capacitor consists of two parallel conductive plates that are not connected but are

electrically separated either by air or by an insulating material called the Dielectric. On

applying a voltage to these plates, current flows charging up the plates with electrons

giving one plate a positive charge and the other plate an equal and opposite negative

charge. This flow of electrons to the plates is known as the charging current and continues

to flow until the voltage across the plates (and hence the capacitor) is equal to the applied

voltage VC.The parallel plate capacitor is the simplest form of capacitor and its

capacitance value is fixed by the equal area of the plates and the distance or separation

between them. Altering any two of these values alters the value of its capacitance and this

forms the basis of operation of the variable capacitors. Unlike other passive devices, there

are several characteristics associated with a capacitor which are useful in selecting a

capacitor for application & categorizing capacitors.

Working Voltage

The Working Voltage is the maximum continuous voltage that can be applied to the

capacitor without failure during its working life. DC and AC values are usually not the

same as the AC value refers to the r.m.s. value. Common working DC voltages are 10V,

16V, 25V, 35V, 63V, 100V, 160V, 250V, 400V and 1000V and are printed onto the body

of the capacitor.

Tolerance, (±%)

This specifies how much the capacitor‘s actual values are nearer to the rated

capacitance with coloured bands or letters. Capacitor‘s tolerance rating is expressed as a

plus-or-minus value

either in Picofarads (±pF) for low value capacitors generally less than 10pF or as a

percentage (±%) for higher value capacitors generally higher than 10pF. The most

common tolerance for capacitors is 5% or 10% but some electrolytic capacitors are rated

as high as 20%.

Leakage Current

The dielectric used inside the capacitor is not a perfect insulator resulting in a very

small current flowing or "leaking" through the dielectric when applied to a constant supply

voltage. This small current flow in the region of micro amps (μA) is called the Leakage


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Current. This leakage current is a result of electrons physically making their way through

the dielectric medium, around its edges or across the leads. The "leakage current" of a

capacitor is sometimes called the "insulation resistance" and can be found using Ohm's

law.

Temperature Coefficient

The Temperature Coefficient of a capacitor is the change in its capacitance with

temperature expressed linearly as parts per million per degree centigrade (PPM/°C), or as

a percent change over a specified temperature range.

Polarization

Polarization generally refers to the electrolytic type capacitors regarding to their

connection. The majority are polarized types, that is the voltage connected to the capacitor

terminals must have the correct polarity, i.e. +ve to +ve and -ve to -ve. Incorrect

polarization can cause the oxide layer inside the capacitor to break down resulting in very

large currents flowing through the device. The majority of electrolytic capacitors have

their -ve terminal clearly marked with a black stripe or black arrows down the side to

prevent any incorrect connection.

Equivalent Series Resistance, (ESR)

The Equivalent Series Resistance is the AC impedance of the capacitor when used

at high frequencies and includes the resistance of the dielectric, plate and terminal leads.

ESR acts like a resistor (less than 0.1Ω) in series with the capacitor and is frequency

dependant.

Film Capacitors

Film Capacitors are the most commonly available type of

capacitor, consisting of a relatively large family of capacitors with the

difference being in their dielectric properties.

These include polyester (Mylar), polystyrene, polypropylene, polycarbonate,

metalized paper, teflon etc. Film type capacitors are available in capacitance ranges from

5pF to 100uF depending upon the actual type of capacitor and its voltage rating. Film

capacitors are generally used for higher power and more precise applications.


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Ceramic Capacitors

Ceramic Capacitors or Disc Capacitors as

they are generally called are made by coating two

sides by a small porcelain or ceramic disc with

silver and are then stacked together to make a

capacitor. For very low capacitance values a single

ceramic disc of about 3-6mm is used. Ceramic

capacitors have a high dielectric constant and are

available so that relatively high capacitances can be

obtained in a small physical size. Ceramic

capacitors have values ranging from a few

picofarads to one or two microfarads but their

voltage ratings are generally quite low.

Ceramic types of capacitors generally have a 3-digit code printed onto their body

to identify their capacitance value. For example, 103 would indicate 10 x 103pF which is

equivalent to 10,000 pF or0.01μF. Likewise, 104 would indicate 10 x 104pF which is

equivalent to 100,000 pF or 0.1μF and so on.

Electrolytic Capacitors

Electrolytic Capacitors are generally used when very large capacitance values are

required. Here instead of using a very thin metallic film layer for one of the electrodes, a

semi-liquid electrolyte solution in the form of a jelly or paste is used which serves as the

second electrode (usually the cathode). The dielectric is a very thin layer of oxide which is

grown electro-chemically in production with the thickness of the film being less than ten

microns. This insulating layer is so thin that it is possible to make large value capacitors of

a small size. The majority of electrolytic types of capacitors are polarized, that is the

voltage applied to the capacitor terminals must be of the correct polarity as an incorrect

polarization will break down the insulating oxide layer and permanent damage may result.

Electrolytic Capacitors are generally used in DC power supply circuits to help

reduce the ripple voltage or for coupling and decoupling applications. Electrolytic's

generally come in two basic forms; Aluminum Electrolytic and Tantalum

Electrolytic capacitors.


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Aluminium Electrolytic Capacitors

There are basically two types of Aluminium Electrolytic Capacitor, the plain foil

type and the etched foil type. The thickness of the aluminium oxide film and high

breakdown voltage give these capacitors very high capacitance values for their size. The

etched foil type differs from the plain foil type in that the aluminium oxide on the anode

and cathode foils has been chemically etched to increase its surface area and permittivity.

This gives a smaller sized capacitor than a plain foil type of equivalent value. Despite, this

type can't withstand high AC currents when compared to the plain type. Also their

tolerance range is quite large up to 20%.

Etched foil electrolytic's are best used in coupling, DC blocking and by-pass

circuits while plain foil types are better suited as smoothing capacitors in power supplies.

Typical values of capacitance range from 1uF to 47000uF. AluminiumElectrolytic's are

"polarized" devices so reversing the applied voltage on the leads will cause the insulating

layer within the capacitor to be destroyed along with the capacitor, "so be aware".

Tantalum Electrolytic Capacitors

Tantalum Electrolytic Capacitors or Tantalum Beads, are available in both wet

(foil) and dry (solid) electrolytic types with the dry (solid tantalum being the most

common). Solid tantalums use manganese dioxide as their second terminal and are

physically smaller than the equivalent aluminium capacitors.

The dielectric properties of tantalum oxide is also

much better than those of aluminium oxide This is because it

gives lower leakage currents and better capacitance stability

which makes them suitable for timing applications. Also

tantalum capacitors although polarized, can tolerate when

connected to a reverse voltage much more easily than the

Aluminium types but are rated at much lower working

voltages. Typical values of capacitance range from 47nF to

470μF.


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INDUCTORS

The Inductor is another passive type electrical component designed to take

advantage of this relationship (a wound coil is to use this magnetic flux to oppose or resist

any changes in electrical current flowing through it) by producing a much stronger

magnetic field than one that would be produced by a simple coil. Inductors are formed

with wire tightly wrapped around a solid central core which can be either a straight

cylindrical rod or a continuous loop or ring to concentrate their magnetic flux. The

schematic symbol for a inductor is that of a coil of wire so therefore, a coil of wire can

also be called an Inductor. Based on the type of core used they are categorized as air core

inductor, iron core inductor, ferrite core inductor & powder core inductors. Variable

inductors, transformers are a few categories of inductors that we commonly use.

Transformer

Its a device that works on the principle of mutual induction that is, it has 2 or more

coils which are used to transfer electrical energy from one circuit to another at different

voltages without changing the frequency. The most commonly used transformer is the

power transformer. A power transformer is used to step up / step down the supply voltage

& current. In step up, the number of turns in primary winding will be less than that in the

secondary winding while in a step down transformer, the number of turns in the secondary

will be less than that of primary winding. So a step up transformer is used for converting

low voltage to high voltage and a step down transformer is used for converting a high

voltage to a low voltage. Transformers are selected & categorized based on certain

specifications such as;

Voltage Rating

It specifies the primary and secondary voltage of the transformer. It depends on the

turns ratio of the windings and is usually expressed in Volts (V).

Current Rating

It specifies the maximum current that the transformer winding can pass through to

the load without any damage for the winding. It is expressed in Amperes (A).

Power Rating

It specifies the maximum amount of power that can be delivered by the transformer

continuously. It is usually expressed in Volts-Ampere (VA).


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Frequency Range

It specifies the frequency range in which the transformer operates without any

failure.

ACTIVE COMPONENTS

SEMICONDUCTOR DIODES

The term semiconductor diode refers to a two electrodes/ terminal device. A

semiconductor diode is a one-way device, offering a low resistance when forward biased,

and behaving almost as an open switch when reverse biased. A normal pn-junction diode

consists of a p-type & n-type semiconductors sandwiched together. The p-side of the diode

is always positive & is termed as anodewhile the n-side of the diode is always negative

and termed as cathode. The circuit diagram of the diode is an arrowhead and bar where the

arrowhead indicates the conventional direction of current flow under forward-biased

They are mainly manufactured of semiconductors such as Silicon &

Germanium. In case of Si, it can be seen that forward current(IF) remains very low until

the forward voltage drop (VF) exceeds the barrier potential (VF≈0.7V). At VF greater than

0.7V, IF increases almost linearly. In case of Ge, VF changes to 0.3V. Since, the reverse

currents are very much smaller than the forward current; the reverse characteristics are

plotted on expanded current scales. For Si diode, IR is normally less than 100nA, and its

almost independent of the reverse-bias voltage. For Ge diodes it falls in the micro-ampere

range. Since, IR is the current due to minority charge carriers; it increases with increasing

reverse-bias voltage. Also, the reverse breakdown voltage of Ge diode is substantially

lower than that of Si diodes.

Taking into account the lower forward voltage drop of Ge diode they has a

distinct advantage but, the lower reverse current and higher reverse breakdown voltage of

Si diodes makes more preferable in applications.


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Some Important Diode Parameters

Peak Reverse Voltage (VR /VRRM) - Max. reverse voltage that can be applied

across the diode.

Steady State Forward current (IO/IF) – Max. current that can be passed

continuously through the diode.

Non-repetitive peak surge current (IFSM) – The maximum current that can be

allowed to flow through the diode when it is switched ON first.

Repetitive current (IFRM) – Peak current that can be repeated over again & again

during the forward biased operation of a diode

Static forward voltage drop (VF) – Max. forward voltage drop for a given

forward current & device temperature.

Continuous power dissipation (PD) – The max. power that the device can safely

dissipate to the surrounding without the device getting damaged.

1N4001 to 1N4007, OA79, BY127, etc are some of the diodes that are popular in the

market. Signal diodes, Rectifier diodes, LED‘s, zener diodes, Photo diodes, etc constitute

the various categories of diodes.

Rectifier Diodes

These diodes are used in rectification processes. These diodes are also called as

low-power diodes. They are usually capable of passing a maximum forward current of 1A

approx. They can also survive a reverse bias up to 500V and their reverse current is

normally less than 1μA at 25°C. 1N4001 to 1N4007 Silicon diodes is an example of

rectifier diodes.

They may be only posses a dimension of 0.3cm long & the cathode can be

identified by a coloured band. These are generally intended for low-frequency

applications.


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Signal Diodes

The Signal Diode is a small non-linear semiconductor devices generally used in

electronic circuits, where small currents or high frequencies are involved such as in radio,

television and digital logic circuits or where a low value of capacitance is required

between the terminals of the device. Signal diodes which are also sometimes known by

their older name Point Contact or Glass Diode. They are physically very small in size and

control small currents. Generally, a signal diode is encapsulated in glass to protect it and

they generally have a red or black band at one end of their body to help identify which end

is its Cathode terminal.

In case of Ge signal diodes, they have a low reverse

resistance value giving a lower forward volt drop across the

junction, typically only about 0.2-0.3v, but have a higher

forward resistance value because of their small junction area.

While for Si signal diodes they have a very high value of

reverse resistance and give a forward volt drop of about 0.6-

0.7v across the junction. They have fairly low values of

forward resistance giving them high peak values of forward

current and reverse voltage.The most widely used of all the

glass encapsulated signal diode is 1N4148 Sisignal diode

&OA79 Ge signal diode.

Zener Diodes

Zener Diodes or "Breakdown Diodes" as they are sometimes called, are basically

the same as the standard junction diode but are specially made to have a low pre-

determined Reverse Breakdown Voltage, called the "Zener Voltage" (VZ). In the forward

direction it behaves just like a normal diode passing current, but when the reverse voltage

applied to it exceeds the selected reverse breakdown voltage, reverse breakdown occurs in

the diode & the current through the diode increases to the maximum circuit value, which is

usually limited by a series resistor.

There are mainly two mechanisms that results in this reverse breakdown in the

reverse biased condition namely; Zener breakdown (on applying a high intensity electric

field across a narrow depletion region, the electrons break away from their atoms thus

converting the insulating depletion to conductor region that is, ionization by electric

field)and Avalanche breakdown (if the depletion region is too wide, then in the presence of


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sufficient reverse bias voltage the electrons in the reverse saturation current collides with

the electrons in the depletion region and thereby cause breakdown to occur that is,

ionization by collision). Usually, zener breakdown occurs at reverse bias less than 5V and

avalanche breakdown occurs at reverse voltage level above 5V.

TRANSISTORS

A bipolar junction transistor (BJT) is simply a sandwich of one type of

semiconductor material (n/p type) between two layers of the opposite type. Hence, there

are basically two configurations of BJT namely; npn&pnptransistors. A small current at

the central region terminal controls the much larger total current flow through the device.

Hence, a transistor can be used for current amplification & voltage amplification.

From the above description, it is clear that a BJT is a three terminal device that is, the

centre layer is known as base (B) and one of the outer layers is referred as emitter (E) and

the other layer as collector (C). BC107, BF195, BC148, SL100, SK100, 2N3055 are some

of commonly used bipolar transistors. The symbolic representations are shown below;


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FIELD EFFECT TRANSISTORS

A field effect transistor (FET) is a unipolar, voltage controlled device which can be

used for amplifiers & switching circuits, similar to a bipolar transistor. Unlike a BJT, a

FET doesn‘t require an input current virtually which results in an extremely high input

resistance; the most prominent advantage of FET over a BJT. There are two categories of

FET namely; Junction FET (JFET) &Metal Oxide Semiconductor FET (MOSFET). These

are further subdivided as p-channel&n-channel devices. In general, a FET has 4 terminals

namely; Source(S),Drain(D), Gate(G) and Shield/Substrate(S). BFW10 & BFW11 are the

popularly used n-channel JFETs.

UNIJUNCTION TRANSISTORS

The unijunction transistor (UJT) consists of a bar of lightly doped n-type silicon with

a block of p-type material on one side. Ohmic contacts are made at the opposite ends of

the n-type bar, one of the terminals is termed as base1 (B1) and base2 (B2) of the

transistor and the p-type rod is termed as emitter (E). Referring to the equivalent circuit,

the resistance of the n-type Si bar is represented by two resistors namely, rB1and rB2. The

summation of these two resistors provides the interbase resistance (RBB) of UJT. The

diode (D1) represents the pn-junction between p-type and n-type semiconductor of the

UJT. The prominent feature considered in application level is the negative resistance

behaviour which is used in designing oscillators. They also play a key role in designing

the firing/ triggering circuits for SCR‘s, in sweep wave generation, etc. 2N2646 is one of

the most commonly used UJT.


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Cables

Solid wire and cable are the oldest forms of electronic transmission media. This

lesson covers three basic types, still in use in building networks, coaxial, unshielded

twisted-pair, and fiber optic. Thin coaxial cable has a core of copper wire and is primarily

used for peer-to-peer LANs due to its low bandwidth and problems with EMI (Electro-

Magnetic Interference). Unshielded twisted-pair cable has twisted pairs of wires as the

core and is divided into five categories, with category 5 used most commonly for building

LANs. Fiber optic cable has a core made of glass and uses light pulses to transmit

information across a network.

Thin Coaxial Cable

Early networks used coaxial cable to connect computers together. Many LANs

were built with coaxial cable. It is often referred to as ThinNet. Coaxial cable has,

A core of copper wire surrounded by a layer of plastic.

A layer of metal mesh.

An outer protective plastic insulation sheath.

Unshielded Twisted-Pair Cable

Unshielded twisted-pair cable is separated into five categories designated bythe

TIA/EIA 568-A standard.

Category 1 is telephone cable.

Category 2 was used for token ring networks and is not recommended for

Ethernet networks.


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Categories 3 and 4 can be used with Ethernet networks, but suffer morefrom EMI

than category 5. Category 3 cables typically have two twists perfoot. Category 4

cables have more twists per foot, but less than Category 5cables. The twisting of

the wires in cables is to help prevent EMI (Electro-Magnetic Interference).

Category 5 cable is primarily used in LANs. The most typical connectorused with

UTP is a RJ-45, which resembles a large telephone connectorRJ-11). This cable

has a very high twist rate per foot.

Fiber-Optic Cable

Fiber optic cable uses light pulses rather than electrical signals to

transmitinformation across a network. The cable may be used over many miles

becausethere is no electrical EMI (Electro-Magnetic Interference) and the bandwidth

isvery high. Fiber optic cable is usually used for the backbone of a network.Since glass

and plastic cores can be cracked or broken, installation requirescare. Special monitoring

equipment is required to locate a break in the fiberoptic cable.


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Connectors

An electrical connector is an electro-mechanical device for joining electrical

circuits as an interface using a mechanical assembly. Connectors consist of plugs (male-

ended) and jacks (female-ended). The connection may be temporary, as for portable

equipment, require a tool for assembly and removal, or serve as a permanent electrical

joint between two wires or devices. An adapter can be used to effectively bring together

dissimilar connectors. There are hundreds of types of electrical connectors. Connectors

may join two lengths of flexible copper wire or cable, or connect a wire or cable to an

electrical terminal

Electrical connectors are characterized by their pin out and physical construction,

size, contact resistance, insulation between pins, ruggedness and resistance to vibration,

resistance to entry of water or other contaminants, resistance to pressure, reliability,

lifetime (number of connect/disconnect operations before failure), and ease of connecting

and disconnecting.

They may be keyed to prevent insertion in the wrong orientation, connecting the

wrong pins to each other, and have locking mechanisms to ensure that they are fully

inserted and cannot work loose or fall out. Some connectors are designed such that certain

pins make contact before others when inserted, and break first on disconnection; this

protects circuits typically in connectors that apply power, e.g. connecting safety

ground first, and sequencing connections properly in hot swapping applications.

It is usually desirable for a connector to be easy to identify visually, rapid to

assemble, require only simple tooling, and be inexpensive. In some cases an equipment

manufacturer might choose a connector specifically because it is not compatible with

those from other sources, allowing control of what may be connected. No single connector

has all the ideal properties; the proliferation of types is a reflection of differing

requirements. Fretting is a common failure mode in electrical connectors that have not

been specifically designed to prevent it.

Keying

Many connectors are keyed, with some mechanical component which prevents

mating except with a correctly oriented matching connector. This can be used to prevent

incorrect or damaging interconnections, either preventing pins from being damaged by

being jammed in at the wrong angle or fitting into imperfectly fitting plugs, or to prevent

damaging connections, such as plugging an audio cable into a power outlet. For

https://en.wikipedia.org/wiki/Electro-mechanical

https://en.wikipedia.org/wiki/Electrical_circuit



https://en.wikipedia.org/wiki/Interface_(computing)

https://en.wikipedia.org/wiki/Copper

https://en.wikipedia.org/wiki/Wire

https://en.wikipedia.org/wiki/Terminal_(electronics)

https://en.wikipedia.org/wiki/Pinout

https://en.wikipedia.org/wiki/Electrical_connector#Power_connectors

https://en.wikipedia.org/wiki/Safety_ground



https://en.wikipedia.org/wiki/Hot_swapping

https://en.wikipedia.org/wiki/Fretting

https://en.wikipedia.org/wiki/Failure_mode


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instance, XLR connectors have a notch to ensure proper orientation, while Mini-

DIN plugs have a plastic projection, which fits into a corresponding hole in the socket and

prevent different connectors from being pushed together (they also have a notched metal

skirt to provide secondary keying).

Plug and socket connectors

Plug and socket connectors are usually made up of a male plug (typically pin

contacts) and a female receptacle (typically socket contacts),

although hermaphroditic connectors exist, such as the original IBM token ring LAN

connector. Plugs generally have one or more pins or prongs that are inserted into openings

in the mating socket. The connection between the mating metal parts must be sufficiently

tight to make a good electrical connection and complete the circuit. When working with

multi-pin connectors, it is helpful to have a pinout diagram to identify the wire or circuit

node connected to each pin.

Component and device connectors

High-power transistor switch module with large screw connectors and small

crimped-on "Fast-on" connectors.Electrical and electronic components and devices

sometimes have plug and socket connectors or terminal blocks, but individual screw

https://en.wikipedia.org/wiki/XLR_connector

https://en.wikipedia.org/wiki/Mini-DIN

https://en.wikipedia.org/wiki/Mini-DIN

https://en.wikipedia.org/wiki/Token_ring

https://en.wikipedia.org/wiki/Pinout


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terminals and fast-on or quick-disconnect terminals are more common. Small components

have bare lead wires for soldering.

Blade connector

A blade connector is a type of single wire connection using a flat conductive blade

which is inserted into a blade receptacle. Usually both blade connector and blade

receptacle have wires attached to them either through of the wire to the blade

or crimping of the blade to the wire. In some cases the blade is an integral manufactured

part of a component (such as a switch or a speaker unit), and a blade receptacle is pushed

onto the blade to form a connection.

A common type of blade connector is the "Faston terminal". While Faston is a trademark

of TE Connectivity (formerly Tyco Electronics), it has come into common usage. Faston

connectors come in male and female types. They have been commonly used since the

1970s.

Ring and spade terminals

The connectors in the top row of the image are known as ring terminals and spade

terminals (sometimes called fork or split ring terminals). Electrical contact is made by the

flat surface of the ring or spade, while mechanically they are attached by passing a screw

or bolt through them. The spade terminal form factor facilitates connections since the

https://en.wikipedia.org/wiki/File:Transistor_Module_01CJC.png

https://en.wikipedia.org/wiki/File:Kabelschuh_verschiedene_commons.jpg


MCET Pathanamthitta

screw or bolt can be left partially screwed in as the spade terminal is removed or attached.

Their sizes can be determined by the size of the conducting wire AWG and the screw/bolt

diameter size designation.

P8C connector

8P8C is short for "eight positions, eight conductors", and so an 8P8C modular

connector (plug or jack) is a modular connector with eight positions, all containing

conductors. The connector is probably most famous for its use in Ethernet and widely used

on CAT5 cables.

The 8P8C modular plugs and jacks look very similar to the plugs and jacks used for

FCC's registered jack RJ45 variants, although the specified RJ45 socket is not compatible

with 8P8C modular plug connectors. It neither uses all eight conductors (but only two of

them for wires plus two for connecting a programming resistor) nor does it fit into 8P8C

because the true RJ45 is "keyed".

https://en.wikipedia.org/wiki/Modular_connector

https://en.wikipedia.org/wiki/Ethernet

https://en.wikipedia.org/wiki/Category_5_cable

https://en.wikipedia.org/wiki/Registered_jack

https://en.wikipedia.org/wiki/File:Ring_wire_end_connector.jpg

https://en.wikipedia.org/wiki/File:EthernetCableBlue2.jpg


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D-subminiature connectors

The D-subminiature electrical connector is commonly used for the RS-232 serial

port on modems and IBM compatible computers. The D-subminiature connector is used in

many different applications, for computers, telecommunications, and test and

measurement instruments. A few examples are monitors (MGA, CGA, EGA),

the Commodore 64, MSX, Apple II, Amiga, and Atari joysticks and mice, and game

consoles such as Atari and Sega.

Another variant of D-subminiature are the Positronic D-subminiature connector

which have PosiBand closed entry contact option, solid machined contacts, thermocouple

contact options, crimp and PCB mount.And the Positronic Combo D-subminiature which

have Large Surface Area (LSA) contact system that is for low contact resistance and saves

energy, and sequential mating options.

USB connectors

The Universal Serial Bus is a serial bus standard to interface devices, founded in

1996. It is currently widely used among PCs, Apple Macintosh and many other devices.

There are several types of USB connectors, and some have been added as the specification

has progressed. The most commonly used is the (male) series "A" plug on peripherals,

when the cable is fixed to the peripheral. If there is no cable fixed to the peripheral, the

peripheral always needs to have a USB "B" socket. In this case a USB "A" plug to a USB

https://en.wikipedia.org/wiki/D-subminiature

https://en.wikipedia.org/wiki/RS-232

https://en.wikipedia.org/wiki/Serial_port



https://en.wikipedia.org/wiki/Modem

https://en.wikipedia.org/wiki/IBM_compatible

https://en.wikipedia.org/wiki/Monochrome_Graphics_Adapter

https://en.wikipedia.org/wiki/Color_Graphics_Adapter

https://en.wikipedia.org/wiki/Enhanced_Graphics_Adapter

https://en.wikipedia.org/wiki/Commodore_64

https://en.wikipedia.org/wiki/MSX

https://en.wikipedia.org/wiki/Apple_II

https://en.wikipedia.org/wiki/Amiga

https://en.wikipedia.org/wiki/Atari

https://en.wikipedia.org/wiki/Sega

https://en.wikipedia.org/wiki/Positronic_(company)

https://en.wikipedia.org/wiki/Personal_computer

https://en.wikipedia.org/wiki/Apple_Macintosh

https://en.wikipedia.org/wiki/Peripheral

https://en.wikipedia.org/wiki/File:9_pin_d-sub_connector_male_closeup.jpg

https://en.wikipedia.org/wiki/File:Type_A_USB_Connecter_alt.jpg


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"B" plug cable would be needed. USB "A" sockets are always used on the host PC and the

USB "B" sockets on the peripherals. It is a 4-pin connector, surrounded by a shield. There

are several other connectors in use, the mini-A, mini- B and mini-AB plug and socket

(added in the On-The-Go Supplement to the USB 2.0 Specification).

Power connectors

Power connectors must protect people from accidental contact with energized

conductors. Power connectors often include a safety ground connection as well as the

power conductors. In larger sizes, these connectors must also safely contain

any arc produced when an energized circuit is disconnected or may require interlocking to

prevent opening a live circuit.

Socket, is the general term, in British English, but there are numerous common

alternatives for household connectors, including power point,plug socket, wall

socket, and wall plug.Receptacle and outlet are common in American English, for

household connectors, sometimes with qualifiers such as wall outlet, electrical

outlet and electrical receptacle.

Radio frequency connectors

Connectors used at radio frequencies must not change the impedance of

the transmission line of which they are part, otherwise signal reflection and losses will

result. A radio-frequency connector must not allow external signals into the circuit, and

must prevent leakage of energy out of the circuit. At lower radio frequencies simple

https://en.wikipedia.org/wiki/AC_power_plugs_and_sockets

https://en.wikipedia.org/wiki/Electric_arc

https://en.wikipedia.org/wiki/Electrical_impedance

https://en.wikipedia.org/wiki/Transmission_line

https://en.wikipedia.org/wiki/Signal_reflection

https://en.wikipedia.org/wiki/RF_connector

https://en.wikipedia.org/wiki/File:IEC60320_C14.jpg

https://en.wikipedia.org/wiki/File:BNC_connector_50_ohm_male.jpg


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connectors can be used with success, but as the radio frequency increases, transmission

line effects become more important, with small impedance variations from connectors

causing the signal to reflect from the connector, rather than to pass through. At UHF and

above, silver-plating of connectors is common to reduce losses. Common types of RF

connectors are used for television receivers, two-way radio, certain Wi-Fi devices with

removable antennas, and industrial or scientific measuring instruments using radio

frequencies.

Relay

A relay is an electrically operated switch. Many relays use an electromagnet to

mechanically operate a switch, but other operating principles are also used, such as solid-

state relays. Relays are used where it is necessary to control a circuit by a low-power

signal (with complete electrical isolation between control and controlled circuits), or

where several circuits must be controlled by one signal. The first relays were used in long

distance telegraph circuits as amplifiers: they repeated the signal coming in from one

circuit and re-transmitted it on another circuit. Relays were used extensively in telephone

exchanges and early computers to perform logical operations.

Simple electromechanical relay




https://en.wikipedia.org/wiki/UHF

https://en.wikipedia.org/wiki/Television

https://en.wikipedia.org/wiki/Two-way_radio

https://en.wikipedia.org/wiki/Wi-Fi

https://en.wikipedia.org/wiki/Electric

https://en.wikipedia.org/wiki/Switch

https://en.wikipedia.org/wiki/Electromagnet

https://en.wikipedia.org/wiki/Solid-state_relay

https://en.wikipedia.org/wiki/Solid-state_relay

https://en.wikipedia.org/wiki/Electrical_telegraph


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Fuse

In electronics and electrical engineering, a fuse is a type of low

resistance resistor that acts as a sacrificial device to provide over current protection, of

either the load or source circuit. It‘s essential component is a metal wire or strip that melts

when too much current flows through it, interrupting the circuit that it connects. Short

circuits, overloading, mismatched loads, or device failure are the prime reasons for

excessive current. Fuses are an alternative to circuit breakers.

Electronic symbols for a fuse.

Switch

A switch responds to an external force to mechanically change an electric signal.

Switches are used to turn electric circuits ON and OFF and to switch electric circuits.

There are many different types of switches. Based on their size, robustness, environmental

resistance and other characteristics, they are divided into switches for industrial equipment

and switches for consumer and commercial devices.

https://en.wikipedia.org/wiki/Electronics

https://en.wikipedia.org/wiki/Electrical_engineering

https://en.wikipedia.org/wiki/Resistor

https://en.wikipedia.org/wiki/Sacrificial_device

https://en.wikipedia.org/wiki/Overcurrent

https://en.wikipedia.org/wiki/Electrical_network

https://en.wikipedia.org/wiki/Short_circuit



https://en.wikipedia.org/wiki/Circuit_breaker

https://en.wikipedia.org/wiki/Electronic_symbol


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Display

A display device (commonly called a display or screen) is an output device for

presentation of information in visualor tactile form (the latter used for example in tactile

electronic displays for blind people). When the input information is supplied as an

electrical signal, the display is called an electronic display

Segment Display

Some displays can show only digits or alphanumeric characters. They are

called segment displays, because they are composed of several segments that switch on

and off to give appearance of desired glyph. The segments are usually single

LEDs or liquid crystals. They are mostly used in digital watches and pocket calculators.

Heat Sink

In electronic systems, a heat sink is a passive heat exchanger that cools a device by

dissipating heat into the surrounding medium. In computers, heat sinks are used to

https://en.wikipedia.org/wiki/Output_device

https://en.wikipedia.org/wiki/Information

https://en.wikipedia.org/wiki/Visual

https://en.wikipedia.org/wiki/Tactile

https://en.wikipedia.org/wiki/Refreshable_Braille_display



https://en.wikipedia.org/wiki/Numerical_digit

https://en.wikipedia.org/wiki/Alphanumeric

https://en.wikipedia.org/wiki/Glyph

https://en.wikipedia.org/wiki/LED

https://en.wikipedia.org/wiki/LCD

https://en.wikipedia.org/wiki/Digital_watch

https://en.wikipedia.org/wiki/Pocket_calculator

https://en.wikipedia.org/wiki/Heat_exchanger


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cool central processing units or graphics processors. Heat sinks are used with high-power

semiconductor devices such as power transistors and optoelectronics such as lasers and

light emitting diodes (LEDs), where the heat dissipation ability of the basic device is

insufficient to moderate its temperature.

https://en.wikipedia.org/wiki/Central_processing_unit

https://en.wikipedia.org/wiki/Graphics_processing_unit

https://en.wikipedia.org/wiki/Transistor


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EXPERIMENT NO: 2

INTRODUCTION TO BS/IEEE SYMBOLS & EDA TOOLS

AIM

To familiarize with various BS/IEE Symbols and EDA tools.

THEORY

In electronic circuits, there are many electronic symbols that are used to represent or

identify a basic electronic or electrical device. They are mostly used to draw a circuit

diagram and are standardized internationally by the IEEE standard (IEEE Std 315) and the

British Standard (BS 3939).

Component Circuit Symbol Description

Wire Wire Circuit Symbol

Used to connect one component to

another.

Wires Joined

Wires Joined Circuit Symbol

One device may be connected to

another through wires. This is

represented by drawing ―blobs‖ on

the point where they are shorted.

Unjoined

Wires

Wires Not Joined Circuit

Symbol

When circuits are drawn some

wires may not touch others. This

can only be shown by bridging

them or by drawing them without

blobs.


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POWER SUPPLIES


Cell

Cell Circuit Symbol

Used to provide a supply for a

circuit.

Battery

Battery Circuit Symbol

A battery has more than a cell and

is used for the same purpose. The

smaller terminal is negative and

the larger one is positive.

Abbreviated as ‗B‘.

DC Supply DC Supply Circuit Symbol

Used as a DC power supply, that

is, the current will always flow in

one direction.

AC Supply

Used as AC power supply, that is,

the current will keep alternating

directions.

Fuse

Used in circuits where a

probability of excessive current

flows. The fuse will break the

circuit if excessive current flows

and saves the other devices from

damage.

Transformer

Used as an ac power supply.

Consists of two coils, the primary

and secondary that are linked

together through an iron core.

There is no physical connection

between the two coils. The

principle of mutual inductance is

used to obtain power.


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Centre Tapped

Transformer

Step Down

Transformer

Step Up

Transformer

Earth/Ground

Earth Circuit Symbol

Used in electronic circuits to

represent the 0 volts of the power

supply. It can also be defined as

the real earth , when it is applied

in radio circuits and power

circuits.

RESISTOR


Resistor Resistor Circuit Symbol

A resistor is used to restrict the

amount of current flow through a

device. Abbreviated as ‗R‘.

Rheostat Rheostat Circuit Symbol

A rheostat is used to control the

current flow with two contacts.

Applicable in controlling lamp

brightness, capacitor charge rate,

etc.

Potentiometer

Potentiometer Circuit

A potentiometer is used to control

the voltage flow and has three

contacts. Have applications in

changing a mechanical angle

change to an electrical parameter.


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Symbol Abbreviated as ‗POT‘.

Preset

Preset Circuit Symbol

Presets are low cost variable

resistors that are used to control the

charge flow with the help of a

screw driver. Applications where

the resistance is determined only at

the end of the circuit design.

CAPACITOR


Capacitor Capacitor Circuit Symbol

Capacitor is a device that is used

to store electrical energy. It

consists of two metals plates that

are separated by a dielectric..

Abbreviated with the letter ‗C‘.

Capacitor –

Polarized

Capacitor-Polarised Circuit

Symbol

Capacitor can be used in a timer

circuit by adding a resistor.

Variable

Capacitor

Variable Capacitor Circuit

Symbol

Used to vary the capacitance by

turning the knob. A type of

variable capacitor is the trimmer

capacitor that is small in size. The

notations are all the same.

DIODE


Diode Diode Circuit Symbol

A diode is used to allow electric

current to flow in only one

direction. Abbreviated as ‗D‘.


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Light Emitting

Diode (LED) LED Circuit Symbol

LED is used to emit light when a

current is passed through the

device. It is abbreviated as LED.

Zener Diode Zener Diode Circuit Symbol

After a breakdown voltage, the

device allows current to flow in

the reverse direction as well. It is

abbreviated as ‗Z‘.

Photo Diode Photo Diode Circuit Symbol

Photodiode works as a photo-

detector and converts light into its

corresponding voltage or current.

TRANSISTOR


NPN

Transistor

Transistor NPN Circuit Symbol

This is a transistor with a layer

of P-doped semiconductor

fixed between two layers of N-

doped semiconductors that act

as the emitter and collector.

Abbreviated as ‗Q‘.

PNP Transistor

Transistor PNP Circuit Symbol

This is a transistor with a layer

of N-doped semiconductor

fixed between two layers of P-

doped semiconductors that act

as the emitter and collector.

Abbreviated as ‗Q‘.

Phototransistor

The working of

a phototransistor is similar to

that of a bipolar transistor with

a difference that it converts

light into its corresponding

current. The phototransistor


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Phototransistor Circuit Symbol can also act as a photodiode if

the emitter is not connected.

Field Effect

Transistor Field Effect Transistor Circuit

Symbol

Like a transistor, a FET has

three terminals, the Gate,

Source and Drain. The device

has an electric field that

controls the conductivity of a

channel of one type charge

carrier in a semiconductor

substance.

N-Channel

Junction FET

n-channel Junction Field Effect

Transistor (JFET) Circuit

Symbol

The Junction Field Effect

Transistor (JFET) is the

simplest type of FET with

applications in Switching and

voltage variable resistor. In an

N-channel JFET an N-type

silicon bar has two smaller

pieces of P-type silicon

material diffused on each sides

of its middle part, forming P-

N junctions.

P-Channel

Junction FET

p-channel Junction Field Effect

Transistor (FET) Circuit Symbol

P-channel JFET is similar in

construction to N-channel

JFET except that P-type

semiconductor base is

sandwiched between two N-

type junctions. In this case

majority carriers are holes.

Metal Oxide

Semiconductor

FET

Abbreviated as

MOSFET. MOSFET is a three

terminal device and is

controlled by a gate bias. It is

known for its low capacitance

and low input impedance.


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Enhancement

MOSFET

e-MOSFET Circuit Symbol

The enhancement MOSFET

structure has no channel

formed during its construction.

Voltage is applied to the gate,

so as to develop a channel of

charge carriers so that a

current results when a voltage

is applied across the drain-

source terminals. Abbreviated

as e-MOSFET.

Depletion

MOSFET

d-MOSFET Circuit Symbol

In the depletion-mode

construction a channel is

physically constructed and a

current between drain and

source is due to voltage

applied across the drain-source

terminals. Abbreviated as d-

MOSFET.

METERS


Voltmeter

Voltmeter Circuit Symbol Voltmeter is used to measure

the voltage at a certain point in

the circuit.

Ammeter

Ammeter Circuit Symbol

An Ammeter is used to

measure the current that passes

through the circuit at a

particular point.

Ohmmeter

Ohmmeter Circuit Symbol Resistance of the circuit is

measured using an Ohmmeter.


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Oscilloscope

Oscilloscope Circuit Symbol

An oscilloscope is used to

measure the voltage and time

period of signals along with

their shape display.

SENSORS


Light

Dependent

Resistor

(LDR)

LDR Circuit Symbol

It is abbreviated as LDR. Light

Dependent Resistor is used to

convert light into its corresponding

resistance. Instead of directly

measuring the light, it senses the

heat content and converts it onto

resistance.

Thermistor Thermistor Circuit Symbol

Instead of directly measuring the

light, a thermistor senses the heat

content and converts it into

resistance. Abbreviated as ‗TH‘.

SWITCHES


Push Switch

Push Switch Circuit Symbol This is an ordinary switch that

passes current only upon

pressing.

Push to Break

Switch

Push to Break Switch Circuit

Symbol

The push to break switch is

usually kept in the ON state

(closed). It turns to OFF state

(open) only when the switch is

pressed.

Singe Pole

Single Throw

Switch

Also known as the ON/OFF

switch. This switch allows the

flow of current only when it is


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On Off Switch (SPST) Circuit

Symbol

kept ON. Abbreviated as SPST.

Single Pole

Double Throw

Switch 2-Way Switch (SPDT) Circuit

Symbol

Also known as the 2-way switch.

It can be also called as an

ON/OFF/ON switch as it has an

OFF position in the center. The

switch causes the flow of current

in two directions, depending on

its position. It can be abbreviated

as SPDT.

Double Pole

Single Throw

Switch

Dual On-Off Switch (DPST)

Circuit Symbol

Abbreviated as DPST. Can also

be called as a dual ON-OFF

switch. This is used to isolate

between the live and neutral

connections in the main electrical

line.

Double Pole

Double Throw

Switch DPDT Circuit Symbol

Abbreviated as DPDT. The

switch uses a central OFF

position and is applied as

reversing switch for motors.

Relay

Relay Circuit Symbol

Relay is abbreviated as ‗RY‘.

This device can easily switch a

230 Volt AC mains circuit. It has

three switching stages called

Normally Open (NO). Normally

Closed (NC), and Common

(COM).

AUDIO AND RADIO DEVICES


Microphone

This device is used for converting

sound to its corresponding

electrical energy. Abbreviated as

http://www.circuitstoday.com/working-of-relays


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Microphone Circuit Symbol ‗MIC‘.

Earphone

Earphone Circuit Symbol Does the reverse process of

microphone and converts electrical

energy into sound.

Loudspeaker

Loudspeaker Circuit Symbol

Does the same operation as an

earphone, but converts an

amplified version of the electrical

energy into its corresponding

sound.

Piezo-

Transducer

PiezoTransducer Circuit

Symbol

It is a transducer that converts

electrical energy into sound.

Amplifier Amplifier Circuit Symbol

Used to amplify a signal. It is

mainly used to represent a whole

circuit rather than just one

component.

Aerial Aerial Circuit Symbol

This device is used to

transmit/receive signals.

Abbreviated as ‗AE‘.

OUTPUT DEVICES


Inductor

Inductor Circuit Symbol

Inductor is used to produce a

magnetic field when a certain current

is passed through a coil of wire. The

wire is coiled on a soft iron core.

Have applications in motors, and

tank circuits. Abbreviated as ‗L‘.


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Motor

Motor Circuit Symbol

This device is used to convert

electrical energy into mechanical

energy. Can be used as a generator as

well. Abbreviated as ‗M‘.

Bell

Bell Circuit Symbol

Used to produce a sound as the

output, according to the electrical

energy produced as the input.

Buzzer

Buzzer Circuit Symbol

It is used to produce an output sound

corresponding to the electrical

energy in the input.

Interpretation of electronic components

The electronic components are interpreted in various methods. Most of the passive

components are interpreted using the color coding schemes and reading the codes printed

on the body of the components. In case of active components we move on to the datasheet

of the component.

Resistor color coding chart

An International resistor colour code scheme was developed many years ago as a

simple and quick way of identifying a resistors value. It consists of coloured rings (in

spectral order) whose meanings are illustrated below:


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SMD RESISTOR READING

CAPACITOR COLOR CODING CHART

Like resistors, small capacitors such as film or disk types conform to the BS1852

Standard where the colours are replaced by a letter or number coded system. The code

consists of 2 or 3 numbers and an optional tolerance letter code. Where a two number code

is used the value of the capacitor only is given in picofarads (ie. 47 = 47 pF). A three letter

code consists of the two value digits and a multiplier much like a resistor colour code (ie.

471 = 47*10 = 47000pF = 47nF)


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The voltage rating of these capacitors are also marked by colour bands but the ratings are

interpreted in different ways depending on the type of capacitor. The details is illustrated

below;

In earlier days, the values of capacitance, voltage or tolerance are marked onto the body of

the capacitors. However, when the value of the capacitance is of a decimal value problems

arise with the marking of a "Decimal Point" as it could easily no be noticed resulting in a

misreading of the actual value. Instead letters such as p (pico) or n (nano) are used in place

of the decimal point to identify its position. For example, a capacitor can be labelled

as, n47 = 0.47nF, 4n7 = 4.7nF or 47n = 47nF.


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Some Coded Capacitor value and their equivalents

Code (pF) (nF) (μF) Code (pF) (nF) (μF)

100 10 0.01 0.00001 472 4700 4.7 0.0047

150 15 0.015 0.000015 502 5000 5.0 0.005

220 22 0.022 0.000022 562 5600 5.6 0.0056

330 33 0.033 0.000033 682 6800 6.8 0.0068

470 47 0.047 0.000047 103 10000 10 0.01

101 100 0.1 0.0001 153 15000 15 0.015

121 120 0.12 0.00012 223 22000 22 0.022

131 130 0.13 0.00013 333 33000 33 0.033

151 150 0.15 0.00015 473 47000 47 0.047

181 180 0.18 0.00018 683 68000 68 0.068

221 220 0.22 0.00022 104 100000 100 0.1

331 330 0.33 0.00033 154 150000 150 0.15

471 470 0.47 0.00047 254 200000 200 0.2

561 560 0.56 0.00056 224 220000 220 0.22

681 680 0.68 0.00068 334 330000 330 0.33

751 750 0.75 0.00075 474 470000 470 0.47

821 820 0.82 0.00082 684 680000 680 0.68

102 1000 1.0 0.001 105 1000000 1000 1.0

152 1500 1.5 0.0015 155 1500000 1500 1.5

202 2000 2.0 0.002 205 2000000 2000 2.0

222 2200 2.2 0.0022 225 2200000 2200 2.2

332 3300 3.3 0.0033 335 3300000 3300 3.3


MCET Pathanamthitta

SMD CAPACITORS

Generally the value is printed on them similar to the resistors.

INDUCTORS

Similar to the resistors and capacitors, the inductors mentioned for usage in electronic

circuits are also standardised using colour coding schemes. In case of military purpose

inductors a Silver banc will be present at the beginning of the bands. The chart below

illustrates the details view of inductor colour coding;

WIRES

Here either colouring or lettering scheme is used for illustrating the purpose for which a

wire can be and is used. The details are mentioned below;


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Wire Lettering – The letters THHN, THWN, THW and XHHN represent the main

insulation types of individual wires. These letters depict the following NEC requirements:.

T – Thermoplastic insulation

H – Heat resistance

HH – High heat resistance (up to 194°F)

W – Suitable for wet locations

N – Nylon coating, resistant to damage by oil or gas

X – Synthetic polymer that is flame-resistant

Color Codes – Different colour wires serve different purposes, like:.

Black : Hot wire, for switches or outlets.

Red : Hot wire, for switch legs. Also for connecting wire between 2 hardwired

smoke detectors.

Blue and Yellow : Hot wires, pulled in conduit. Blue for 3-4 way switch

application, and yellow for switch legs to control fan, lights etc.

White : Always neutral.

Green and Bare Copper : Only for grounding.

INTERPRETATION OF ACTIVE COMPONENTS

Unlike passive components, the Part number is an essential part of the active component

identification process.Depending on where the parts are made the part numbers will mean

somethingdifferent. Theyrepresent information that is important to the way the device is

used. Forexample, what material the device is made out of, applications it can beused for,

and a series of number that distinguish that part from all others soone can find device

specifications and parts that may be compatible with thepart that is being looked up.There

are many systems in use such as the European based Pro-electron system, the American

based JEDEC system and the Japanese based JIS system and Major

manufacturersintroduce their own schemes as well

1.1 Pro-electron standard

The European semiconductor standard Pro-Electro was set up in 1966 in Brussels,

Belgium. In 1983 it was merged with the European Electronic Component Manufacturers

Association (EECA) and since then operates as an agency of the EECA. This system uses

the following format;

Two letters, serial number, [suffix]


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The 1st letter specifies the semiconductor material

A - Germanium

B - Silicon

C - Gallium Arsenide

R - Compound Materials

The 2nd

letter specifies the type of device

A - Diode, low power or signal

B - Diode, variable capacitance

C - Transistor, audio frequency low power

D - Transistor, audio frequency power

E - Diode, tunnel

F - Transistor, high frequency low power

G - Miscellaneous devices

H - Diode, sensitive to magnetism

K - Hall effect device

L - Transistor, high frequency power

N - Photo coupler

P - Light detector

Q - Light emitter

R - Switching device, low power e.g. Thyristors, diac, UJT,etc

S - Transistor, low power switching

T - Switching device power, e.g. Thyristors, triac, etc

U - Transistor, switching power

W - Surface acoustic wave device

X - Diode, multiplier, e.g. varactor

Y - Diode, rectifying

Z -Diode, voltage reference

Serial Number - The serial number runs from 100-9999.

Suffix - If a suffix is present then this indicates the gain group as below;

A - Low gain

B - Medium gain


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C - High gain

For example, AC107 would be a Ge, Transistor used for low power audio frequency

application.

1.2 Joint Electron Devices Engineering Council (JEDEC)

The JEDEC Solid State Technology Association, formerly known as the Joint

Electron Devices Engineering Council (JEDEC), is an independent semiconductor

engineering trade organization and standardization body. Associated with the Electronic

Industries Alliance (EIA), a trade association that represents all areas of

the electronics industry in the United States, JEDEC has over 300 members, including

some of the world's largest computer companies.This system has the following format;

Digit, letter, serial number, [suffix]

Digit-The first digit designates the amount of P-N junctions in the device. So a device

starting with "2" would contain 2 P-N junctions and would most likely be either a

transistor or a FET. Common part numbers are listed below;

1 - Diodes

2 - Bipolar transistors or Field Effect Transistors

3 - Double Gate MOSFETS, SCR's

4 - Opto Couplers

Letter-The letter is always "N", and the remaining figures contain the device serial

number.

Serial Number -The serial number runs from 100 to 9999 and indicates nothing about the

transistor.

Suffix -If a suffix is present then this indicates the gain group as below;

A - Low gain

B - Medium gain

C - High gain

For example, 1N4001 would be a diode and 3N201 would be a double gate MOSFET.

1.3 Japanese Industrial Standard (JIS)

The Japanese Industrial Standard has the following format;

Digit, two letters, serial number, [suffix]

Digit -This indicates the amount of p-n junctions as in the JEDEC code.


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Letters -The letters indicate the intended application for the device according to the

following code;

SA - PNP HF transistor

SB - PNP AF transistor

SC - NPN HF transistor

SD - NPN AF transistor

SE - Diodes

SF - Thyristors

SG - Gunn devices

SH - UJT

SJ - P-channel FET/MOSFET

SK - N-channel FET/MOSFET

SM - Triac

SQ - LED

SR - Rectifier

SS - Signal diodes

ST - Diodes

SV - Varicaps

SZ - Zener diodes

Serial Number -The serial number runs from 10-9999.

Suffix -The (optional) suffix indicates that the type is approved for use by various

Japanese organizations.


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Major Manufacturers

Major manufacturers often produce their own code and numbering scheme for

commercial reasons. The following abbreviations represent some of the larger

semiconductor manufacturers;

MJ - Motorola power, metal case

MJE - Motorola power, plastic case

MPS - Motorola low power, plastic case

MRF - Motorola HF, VHF and microwave transistor

TIP - Texas Instruments power transistor (plastic case)

TIPL - TI planar power transistor

TIS - TI small signal transistor (plastic case)

Common examples include: TIP32A, MJE3055, ZTX302.

Because of the late standardization of the European semiconductor devices many

different codes were used by a several manufactures, the code their used was most of the

time brand specified. Some examples are AEI/BTH (GT and S numbering), Mullard (OA,

OC series, STC/Brimar (M, GD, JK and TK series), Ediswan ( EFT, XA, XB and XC

series), GEC (EW, S and SX series), New Markert (V, NKT series) and so on.


MCET Pathanamthitta

Typical Component Datasheets

Datasheet of Standard Recovery Rectifier Diodes1N4001 thru 1N4007

Features:-

Subminiature size

Axial Lead mounted rectifiers

Used in general purpose low-power applications

Approx. 0.4gram weight

Cathode indicated by polarity band

MAXIMUM RATINGS

Parameter Symbol 1N40

01

1N40

02

1N40

03

1N40

04

1N40

05

1N40

06

1N40

07

Peak Repetitive

Reverse voltage

DC Blocking

Voltage

VRRM

VR 50V 100V 200V 400V 600V 800V

1000

V

Non-Repetitive

Peak Reverse

Voltage

VRSM 60V 120V 240V 480V 720V 1000

V

1200

V

RMS Reverse

voltage VR(RMS) 35V 70V 140V 280V 420V 560V 700V

Average Rectified

Forward Current IO 1 Amp

Non-Repetitive

Peak Surge Current IFSM 30 Amp (1 cycle)

Operating

Temperature Range TJ / Tstg -65

OC - +175

OC

ELECTRICAL CHARACTERISTICS

Parameter Symbol Typ. Max. Unit

Maximum Instantaneous Forward Voltage

Drop VF 0.93 1.1 Volts

Maximum Full cycle Average forward

Voltage Drop VF(AV) --- 0.8 Volts

Maximum Reverse Current IR 0.05 10 A

Maximum Full-Cycle Average Reverse

Current IR(AV) --- 30 A

Datasheet of ZenerDiodes1N746 thru 1N759

Features:-


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Silicon planar power diodes

Tolerance 10%, suffix ‗A‘ for 5%

Color band indicates cathode end.

MAXIMUM RATINGS

Parameter Symbol Value Unit

Power Dissipation PO 500 mW

Junction Temperature TJ 175 O

C

Storage Temperature Range TSTG -65 to 200 O

C

Forward Voltage VF 1.5 V


Device VZ (V) IZT (mA) ZZR () IR (A)

TA = 25C

IR (A)

TA =

150C

IZRM/IZM

(mA)

1N746 3.3 20 28 10 30 110

1N747 3.6 20 24 10 30 100

1N748 3.9 20 23 10 30 95

1N749 4.3 20 22 2 30 85

1N750 4.7 20 19 2 30 75

1N751 5.1 20 17 1 20 70

1N752 5.6 20 11 1 20 65

1N753 6.2 20 7 0.1 20 60

1N754 6.8 20 5 0.1 20 55

1N755 7.5 20 6 0.1 20 60

1N756 8.2 20 8 0.1 20 45

1N757 9.1 20 10 0.1 20 40

1N758 10.0 20 17 0.1 20 35

1N759 12.0 20 30 0.1 20 38

Datasheet of NPN General Purpose TransistorsBC 107A/ BC 107B/ BC 107C

Features:-

Silicon planar epitaxial NPN transistors.

Suitable in driver stages, signal processing circuits,low noise amplification,

switching & low noise input stages.

MAXIMUM RATINGS


Collector Base Voltage (IE = 0) VCBO 50 V


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Collector Emitter Voltage (IB = 0) VCEO 45 V

Emitter – Base Voltage (IC = 0) VEBO 6 V

Collector Current (DC) IC 100 mA

Peak Collector Current ICM 200 mA

Peak Base Current IBM 200 mA

Total Power Dissipation PTOT 0.3 W

Operating Junction Temperature TJ 200 C


Parameter Symbol Min. Typ. Max. Unit

Collector Base Breakdown Voltage (IE = 0) V(BR)CB

O

50 V

Collector Emitter Breakdown Voltage (IB =

0)

V(BR)CE

O

45 V

Emitter – Base Breakdown Voltage (IC = 0) V(BR)EB

O

6 V

Collector Cut-off Current (IE = 0) ICBO 15 nA

Collector Emitter Saturation Voltage (IC =

10mA, IB = 0.5mA)

VCE(sat) 70 250 mV

Base Emitter Saturation Voltage (IC =

10mA, IB = 0.5mA)

VBE(sat) 750 mV

Base Emitter On Voltage (IC = 2mA, VCE =

5V)

VBE(ON) 550 650 700 mV

DC Current Gain (IC = 2mA, VCE = 5V)

BC107A

BC107B

hFE 110

200

180

290

220

450

Small signal Current Gain (IC = 2mA, VCE

= 5V)

BC107A

BC107B

hfe 250

300

Collector Base Capacitance (IE = 0, VCB =

10V)

CCBO 4 6 pF

Emitter Base Capacitance (IC = 0, VEB =

0.5V)

CEBO 12 pF

Input Impedance (IC = 2mA, VCE = 5V)

BC107A

BC107B

hie 4

4.8

K

K

Reverse Voltage Ratio (IC = 2mA, VCE =

5V)

BC107A

BC107B

hre 2.2 x

10-4

2.7 x

10-4

Output Admittance (IC = 2mA, VCE = 5V)

BC107A

BC107B

hoe 30

26

S

S


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Datasheet of NPN Epitaxial Silicon TransistorsBC 547/550

Features:-

Silicon epitaxial NPN transistors.

Suitable for low noise amplification switching applications.

MAXIMUM RATINGS


Collector Base Voltage VCBO 50 V

Collector Emitter Voltage VCEO 45 V

Emitter – Base Voltage VEBO 6 V


Collector Power Dissipation PC 500 mW

Storage Temperature TSTG -65 to 150 C




Collector Cut-off Current (IE = 0, VCB =

30V) ICBO 15 nA

Collector Emitter Saturation Voltage

(IC = 10mA, IB = 0.5mA) VCE(sat) 90 250 mV

Base Emitter Saturation Voltage

(IC = 10mA, IB = 0.5mA) VBE(sat) 700 mV

Base Emitter On Voltage (IC = 2mA, VCE

= 5V) VBE(ON) 580 660 700 mV


BC 547A/ BC 550A

BC 547B/ BC 550B

BC547C/ BC 550C

hFE

110

200

420

220

450

800

Output Capacitance (IE = 0, VCB = 10V) Cob 3.5 6 pF

Input Capacitance (IC = 0, VEB = 0.5V) Cib 9 pF

Current gain Bandwidth Product fT 300 MHz

Datasheet of NPN Silicon TransistorsBC 194/195

Features:-


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Suitable for IF & RF applications.

MAXIMUM RATINGS






Total Power Dissipation PD 250 mW





Collector Base Breakdown Voltage BVCBO 30 V

Collector Emitter Breakdown Voltage BVCEO 20 V

Emitter – Base Breakdown Voltage BVEBO 5 V

Base Emitter On Voltage (IC = 1mA, VCE =

10V) VBE(ON) 0.65 0.74 V


BF 195D

BF 195C

BF 194B

hFE

38

71

110

71

110

200

Common Emitter Feedback Capacitance (IC

= 1mA, VCE = 10V) Cre 0.95 pF

Current gain Bandwidth Product fT 260 MHz


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Datasheet of NPN Silicon Medium Power Transistors SL100

Features:-

Suitable for general purpose medium power applications.

MAXIMUM RATINGS










Parameter Symbol Min. Max. Unit




Collector Cut-off Current ICBO 50 nA

Emitter Cut-off Current IEBO 25 nA

Collector Emitter Saturation Voltage VCE(sat) 0.6 V

Base Emitter Saturation Voltage VBE(sat) 1.3 V

Output capacitance Cob 20 pF

DC Current Gain (IC = 10mA, VCE =

10V)

SL100

SL100B

hFE 25

100

100

300


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Datasheet of PNP Silicon Medium Power Transistors SK100

Features:-

Suitable for general purpose medium power applications.

MAXIMUM RATINGS










NB: Polarity of voltages & currents are complementary of SL100

Datasheet of PNP Silicon Power Transistors 2N3055

Features:-

Silicon epitaxial-base planar NPN transistor.

Suitable for power switching circuits, high fidelity amplifiers, usage in series &

shunt regulators.

MAXIMUM RATINGS





Collector Current IC 15 A

Parameter Symbol Min. Max. Unit




Collector Cut-off Current ICBO 50 nA

Emitter Cut-off Current IEBO 25 nA

Collector Emitter Saturation Voltage VCE(sat) 0.6 V

Base Emitter Saturation Voltage VBE(sat) 1.3 V

Output capacitance Cob 20 pF


SL100

SL100B

hFE 25

100

100

300


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Base Current IB 7 A

Total Power Dissipation PD 115 W




NB: Complementary power transistor MJ2955. Values of parameters are the same

but the polarity gets reversed.

Datasheet of Silicon PN Junction Transistors2N2646 / 2N2647

Features:-

Low Peak Point Current & Emitter Reverse Current

Passivated Surface for Reliability and Uniformity

Used in pulse and timing circuits, sensing circuits and thyristor trigger circuits.

MAXIMUM RATINGS


Power Dissipation PD 300 mW

RMS Emitter Current IE(RMS) 50 mA

Peak Pulse Current IE 2 A

Emitter Reverse voltage VB2E 30 V

Interbase voltage VB2B1 35 V

Operating Temperature TJ -65 to 125 C



Intrinsic Stand-off Ratio

2N2646

2N2647

0.56

0.68

0.63

0.72

0.82

Parameter Symb

ol

Min. Max. Unit

Collector Emitter Sustaining Voltage VCEO(

sus)

60 V

Collector Cut-off Current ICEO 0.7 mA

Emitter Cut-off Current IEBO 5 mA

Collector Emitter Saturation Voltage VCE(sa

t)

0.6 V

Base Emitter ON Voltage VBE(O

N)

1.5 V

Second Breakdown Collector Current with

forward biased Base.

IS/B 2.87 A

DC Current Gain (IC = 10mA, VCE = 10V) hFE 20 70

Small signal Current gain hfe 15 120


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Interbase resistance rBB 4.7 7 9.1 K

Emitter Saturation voltage VEB1(sat) 3.5 V

Interbase modulated current IB2(mod) 20 mA

Emitter reverse current IEB2O 0.005 12 A

Peak point emitter current

2N2646

2N2647

IP 1

1

5

2

A

A

Valley point emitter current

2N2646

2N2647

IV 4

8

6

10 18

mA

mA

Base 1 peak pulse voltage

2N2646

2N2647

VOB1 3

6

5

7

V

V

Datasheet of n-channel depletion – JFETBFW10/BFW11

Features:-

Suitable for VHF/UHF amplification process.

MAXIMUM RATINGS


Drain Source voltage VDS 30 V

Drain Gate voltage VDG 30 V

Reverse Gate-source voltage VGSR -30 V

Forward gate current IG 10 mA

Total power dissipation PD 300 mW

Operation Temperature TJ -65 to 150 C



Gate Source Breakdown Voltage

(IG = 10A) BVGSS 30 V

Gate Source Cut-off voltage (VDS

= 15V)

2N2646

2N2647

VGS(off) 8

6 V

Gate source voltage (VDS = 15V)

2N2646

2N2647

VGS 2

1.25

7.5

4 V

Gate reverse current (VGS = 20V) IGSS 0.1 nA


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Drain Saturation Current (VDS =

15V)

2N2646

2N2647

IDSS 8

4

20

10 mA

Forward trans admittance (VDS =

15V)

2N2646

2N2647

Yfs 3.5

3

6.5

6.5 mmho

Output Admittance (VDS = 15V)

2N2646

2N2647

Yos 85

50 mho

Input Capacitance (VDS = 15V) Ciss 5 pF

Reverse transfer capacitance (VDS

= 15V) Crss 0.8 pF

Forward trans admittance (VDS =

15V) Yfs 3.2 mmho

Datasheet of plastic molded SCR2P4M/2P5M/2P6M

Features:-

Miniature size, easy to install.

Less holding current.

Used in various applications such as temperature control, speed control of

miniature motors, lamp dimmer, battery charger, solid state static switches, etc.

MAXIMUM RATINGS


Non repetitive Peak Reverse Voltage VRSM 500 V

Non repetitive Peak Off State Voltage VDSM 500 V

Repetitive Peak Reverse Voltage VRRM 400 V

Repetitive Peak Off State Voltage VDRM 400 V

On state Current IT(AV) 2 A

Peak Gate power Dissipation PGM 0.5 W

Average gate power dissipation PGM(AV) 0.1 W

Peak Gate forward current IFGM 0.2 A

Peak Gate reverse voltage VRGM 6 V



Repetitive Peak Reverse Current IRRM 100 A


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Repetitive Peak Off-state Current IDRM 100 A

On state voltage VTM 2.2 V

Gate trigger current IGT 200 A

Gate trigger voltage VGT 0.8 V

Gate non-trigger voltage VGD 0.2 V

Critical rate of rise of Off-state

voltage dv/dt 10 V/S

Holding Current IH 1 3 mA

Datasheet of Glass Passivated SCRTYN 204 ---- TYN 1004

Features:-

High On-State Current.

Highly stable, reliable & surge capable.

Used in power supplies with 400Hz with resistive load or inductive load.

MAXIMUM RATINGS


RMS on-state current ITRSM 4 A

Non repetitive surge Peak On State Current ITSM 60 A

Repetitive Peak Reverse Voltage VRRM 200 V

Repetitive Peak Off State Voltage VDRM 200 V

On state Current IT(AV) 2.5 A


Parameter Symbo

l Min. Typ. Max. Unit

Repetitive Peak Reverse

Current IRRM 0.01 mA

Repetitive Peak Off-state

Current IDRM 0.01 mA

On state voltage VTM 1.8 V

Gate trigger current IGT 15 mA

Gate trigger voltage VGT 1.5 V

Gate non-trigger voltage VGD 0.2 V

Critical rate of rise of Off-state

voltage dv/dt 200 V/S

Holding Current IH 30 mA

Critical rate of rise of on-state

current di/dt 100 A/S

Datasheet of TIMER ICLM/NE/SA 555


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MAXIMUM RATINGS


Supply Voltage VCC 16 V

Lead Temperature TLEAD 300 C


Operating temperature Toperating -40 to 85 C


Parameter Symbo


Supply Voltage VCC 4.5 16 V

Supply Current ICC 3 6 15 mA

Control Voltage VC 2.6 9 11 V

Threshold Voltage VTH 3.33 10 V

Threshold Current ITH 0.1 0.25 A

Trigger Voltage VTR 1.1 5 5.6 V

Trigger Current ITR 0.01 2 A

Reset Voltage VRST 0.4 0.7 1 V

Reset Current IRST 0.1 0.4 mA

Low Output voltage VOL 0.06 0.25 V

High Output voltage VOH 12.75 12.5 13.3 V

Rise Time of Output tR 100 ns

Fall Time of Output tF 100 ns

Datasheet of General Purpose Op-Amp

A741C/ A741I /A741M

MAXIMUM RATINGS


Supply Voltage

A741C VCC

18

22 V


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A741I

A741M

22

Differential input voltage

A741C

A741I

A741M

VID

15

30

30

V

Input voltage

A741C

A741I

A741M

VI

15

15

15

V

Voltage between offset null & -VCC

A741C

A741I

A741M

15

0.5

0.5

V


Operating temperature Toperating -65 to

150 C



Input offset voltage

A741C

A741I/A741M

VIO 1

1

6

5 mV

Adjustable offset voltage range

A741C/ A741I /A741M VIO 15 mV

Input offset current

A741C/ A741I /A741M IIO 20 200 nA

Input bias current

A741C/ A741I /A741M Ibias 80 500 nA

Common mode input voltage

range

A741C/ A741I /A741M

VICR 12 13 V

Parameter Symbo


Max. peak output voltage swing

A741C/ A741I /A741M VOP 12 13 14 V

Large signal differential voltage

amplification

A741C

A741I /A741M

AD 20

50

200

200 V/mV

Input resistance

A741C/ A741I /A741M ri 0.3 2 M


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Output resistance

A741C/ A741I /A741M ro 75

Input capacitance

A741C/ A741I /A741M Ci 1.4 pF

CMRR (Common Mode Rejection

Ratio)

A741C/ A741I /A741M

CMRR 70 90 dB

Supply voltage sensitivity

A741C/ A741I /A741M KSVS 30 150 V/V

Short circuit output current

A741C/ A741I /A741M IOS 25 40 mA

Supply current (No load)

A741C/ A741I /A741M ICC 1.7 2.8 mA

Power dissipation (without load)

A741C/ A741I /A741M PD 50 85 mW

Slew rate at unity gain

A741C/ A741I /A741M SR 0.5 V/s


MCET Pathanamthitta

INTRODUCTION TO EDA TOOL AND DRAWING SCHEMATIC

Electronic Design Automation (EDA) is the category of tools for designing and

producing electronic systems ranging from printed circuit boards (PCBs) to integrated

circuits. This is sometimes referred to as ECAD (electronic computer-aided design) or just

CAD. These tools work together in a design flow that chip designers use to design and

analyze entire semiconductor chips. Before EDA, integrated circuits were designed by

hand, and manually laid out. The process was fundamentally graphic, with the translation

from electronics to graphics done manually. By the mid-1970s, developers started to

automate the design along with the drafting. The first placement and routing tools were

developed. The next era began about the time of the publication of "Introduction

to VLSI Systems" by Carver Mead and Lynn Conway in 1980. This ground breaking text

advocated chip design with programming languages that compiled to silicon. The

immediate result was a considerable increase in the complexity of the chips that could be

designed, with improved access to design verification tools that used logic simulation.

Although the languages and tools have evolved, this general approach of specifying the

desired behavior in a textual programming language and letting the tools derive the

detailed physical design remains the basis of digital IC design today.

The earliest EDA tools were produced academically. One of the most famous was the

"Berkeley VLSI Tools Tarball", a set of UNIX utilities used to design early VLSI systems

and still Espresso heuristic logic minimizer and Magic are widely used. 1981 marks the

beginning of EDA as an industry where the larger electronic companies, such as Hewlett

Packard, Tektronix, and Intelpursued EDA tools internally. Current digital flows are

extremely modular. The front ends produce standardized design descriptions that compile

into invocations of "cells‖ without regard to the cell technology. Cells implement logic or

other electronic functions using a particular integrated circuit technology. Fabricators

generally provide libraries of components for their production processes, with simulation

models that fit standard simulation tools.

Analog EDA tools are far less modular, since many more functions are required, they

interact more strongly, and the components are less ideal (in general). EDA tools for

electronics has rapidly increased in importance with the continuous scaling

of semiconductor technology.EDA tools are also used for programming design

functionality into FPGAs.

Proteus is an ECAD tool for microprocessor simulation, schematic capture, and printed

circuit board (PCB) design with many more features developed and marketed by

Labcenter Electronics. Proteus PCB design combines the ISIS schematic capture and

ARES PCB layout programs to provide a powerful, integrated and easy to use suite of

tools for professional PCB Design. Its simplicity and user friendly design made it popular

among electronics hobbyists. Proteus is commonly used for digital simulations such as


MCET Pathanamthitta

microcontrollers and microprocessors and also enables emulation of LED, LDR, USB

Communication

Getting Started with Proteus ECAD Tool

In case of Proteus tool‘s versions below 8 the process to start was very simple since, ISIS

Schematic Capture and ARES PCB Layout were two independent parts of the same tool.

To initiate a schematic/ PCB layout design you have to just double click on the

corresponding icons.

To save the projects in ISIS Schematic Capture and ARES PCB Layout we need to use the

option File Save Design and Save Layout respectively.

While we move on to the higher versions like Proteus 8 Professional and higher the steps

are little different. From the Proteus 8 Professional version onwards all the facilities are

linked together. The below steps describes the step-by-step procedure to get started with

Proteus 8 Professional version;

1. Double click on the Proteus 8 Professional icon in the desktop or select the same

for the Start Menu.

2. The Home page of the tool opens up. Select File New Project


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3. Now the New Project Wizard pops up where you can enter the name of the project,

location of saving the project. Also you can select the option either to start a project from

scratch or to enhance the project from an existing development board project.

4. Once the selection is made you can click Next (here it‘s have considered New

project). Then the next dialog box opens which asks you whether you need to draw a

schematic. If you just need to a PCB layout only no need of drawing the schematic then

you can click Next without making any changes. Once schematic creation is selected then

the template size is selected (Generally DEFAULT).


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5. On clicking Next, the dialog box proceeds and asks whether you need to include

PCB layout design for the project. Similar to the case of schematic here also you can

make the required decision and proceed further. On selecting the PCB layout design

addition then you can select an appropriate template (Generally DEFAULT).

6. Now the dialog box proceeds and prompts whether you need to add a firmware or

not. The selection of firmware is normally selected when we need to simulate a

microcontroller project, such that coding and compiling can be done using Proteus itself.


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7. Now the dialog box proceeds and displays the summary of the options included in

the project and the locations in which they are saved.

8. Click on Finish, if the project creation was as per your wish or if you need to make

any alterations go Back and make it and proceed again and click Finish.

Getting Started with ISIS Schematic Capture

Open the ‗ISIS Professional‘ from PROTEUS. This is the application where the

simulations of the circuits can be tested. But the same file can be further processed to

transform it into a layout. Layout is the final design which is needed in order to make the


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PCB of a circuit. To make the schematic, first we must have its raw design. For this, after

installing Proteus, run ISIS/ISIS Professional hence the following window appears;

The main window consists of various parts, a brief description of each part is mentioned

below;

1. Schematic Editor window / Editing Window:

This is the space used to draw the schematic. Blue box indicates the

editable area, we must place/put the components inside it. Note that this window

doesn‘t contain any scroll bar, you can use the preview window on the top left

corner to change the schematic visual range. The size of the editable area can be

changed by selecting the option Set Sheet size from the System Menu.

2. Preview window / Overview Window:

The space on the left side of the window aside of the mode selection

toolbar. It performs separate functions namely in component mode and editor

mode. When you are in the component mode, the list of components selected will

be displayed and when we select a component, the preview of the element will be

shown in the preview window. Once we enter to the editor mode and when the

mouse focus falls on the principle diagram editor window that is, place the

component into the schematic editor window or click the mouse in the Editing

window, the preview window will display the entire schematic diagram as a

thumbnail. The content of the current diagram will be denoted by a green box in

the preview window. You can use the mouse to click on it to change the location of

the green box, thereby changing the schematic visual range.


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3. Model Selection Toolbar (Mode Selector Toolbar):

a. Main Modes:

1. Select elements/ components. (Selected by default)

2. Place the connection point

3. Place a label (Used in case of use of bus in schematic)

4. Place text

5. Drawing bus

6. Placing subcircuits

7. Enables instant editing component parameters ( first click on the icon

and then click the element you want to modify )

b. Tools:

1. Terminal interface (terminals) – You can select VCC, ground, output,

input and other interfaces by entering this mode.

2. Device Pin : for drawing pin

3. Emulation chart (graph) - Used while performing various analyzes,

such as Noise Analysis, etc.


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4. Recorder

5. Signal generator.

6. Voltage Probe - Used along with simulation charts

7. Current probe - Used along with simulation charts

8. Virtual Instrument – Used for placing instruments like CRO, Logic

Analyzer, etc.

c. 2D graphics (2D Graphics):

1. Draw line

2. Draw box

3. Draw circle

4. Draw arc

5. Draw polygons

6. Draw text

7. Draw symbols

8. Paintings, origin, etc.

4. Component List (The Object Selector):

This lists out the selected components while in Component mode, list out the

various terminal interface available when you enter the Terminals mode, list out

the various signal generators available when you enter the Generators mode, list

out the various charts/graphs available when you enter the Graph mode and so on.

For example , when you select Components mode from the mode selector tool bar

and click the " P " button which opens a component selection dialog box, select an

element and click on the " OK ". Then the device/component selected will be

displayed in the list of elements, later you can use this element in the component

list by entering to component mode and clicking on the element in the list.

5. Toolbars direction (Orientation Toolbar):

a. Rotate :

The rotation angle can be an integer multiple of 90 .

b. Flip:

Flip Horizontal and vertical flip. Right-click the

component , and then click the corresponding rotation icon.

6. Simulation Toolbar

1. Run

2. Single-step operation

3. Pause

4. Stop

7. Selecting the components


MCET Pathanamthitta

a. Click the "P" button in the Component List/Object Selector, then a

Component dialog box appears

8.

b. In the Keywords box of the dialog box , enter the name of the component

required Eg: ATMEGA16, then it produces the following results :

http://www.youspice.com/MTF/Content/pagine/Proteus_page31_image2.jpg



MCET Pathanamthitta

8. Once you find the preview of the component arrives in the dialog box then you can

Click OK, and close the dialog box , then the components listed in the list

ATMEGA16.

9. Place all the required components and the component list gets updated like;

10. To place the place to the schematic area select the required component in the

component list and left click in the schematic editor window, so that the

component will be placed in the Schematic Editor window. Similarly place all the

components to the schematic editor window.

11. To add Ground & VCC to the schematic select the terminals icon from the mode

selector toolbar then the dialog displaying the available terminal points will appear;

12. Click on GROUND, and left-click in the schematic editor window, so that the

"ground" will be placed into the Schematic Editor window.

13. While placing components pay attention to place them inside the blue box of work

area.

14. To make connection just bring the cursor to the tip of the pins available on the

components placed, then you can see the tip changes its icon shape from arrow to

pencil. Click on that point and move the cursor to the destination node/pin tip and



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click again once you have reached the destination tip/node point. You can see that

the cursor icon shape has re-transformed to arrow icon. By default, VSS, VDD,

VEE don't need connections , the default VSS = 0V, VDD = 5V, VEE =-5V, GND

= 0V

To delete/move any connections or components, select edit icon for mode selector toolbar

and click on the desired component/connections and perform the required action by

pressing DELETE button/ drag the component/connections.


MCET Pathanamthitta

EXPERIMENT NO:3

FAMILIARISATION OF TESTING INSTRUMENTS AND COMMONLY USED TOOLS

AIM

To familiarize with various Electronics Laboratory instruments and tools.

Laboratory instruments,

Cathode Ray Oscilloscope

Function Generator

Digital Multimeter

Power supply

Tools

Soldering iron

De soldering pump

Pliers

Cutters

Wire strippers

Screw drivers

Tweezers

Crimping tool

Hot air soldering and de soldering station

THEORY

Cathode Ray Oscilloscope (CRO)

The CRO is an extremely useful and most versatile laboratory instrument used for

studying wave shapes of alternating currents & voltages as well as for measurement of

voltage, current, power and frequency; in fact, almost any quantity involves amplitude and

waveforms. It allows the user to see the amplitude of electrical signals as a function of

time on the CRT screen. In most applications, the graph shows how signals change over

time: the vertical (Y) axis represents voltage and the horizontal (X) axis represents time.

The display consists of a tube with an electron gun, x and y-deflection plates, and a

phosphor screen which glows in response to an internal electron beam. In normal


MCET Pathanamthitta

operation the beam is swept continuously from left to right at a uniform speed. A triggered

ramp generator generates this sweep motion by applying a "saw-tooth" voltage to the x-

deflection plates. The sweep rate and method of triggering can be varied using controls on

the front panel. An external voltage connected to one of the oscilloscope inputs can be

internally amplified and applied to the y-deflection plates. The combination of the x and y-

motions then causes the beam to trace out a plot of the input voltage as a function of

time.The four main scope control areas are: 1) display controls, 2) input amplifiers, 3)

trigger selection, 4) time base setting.

The compact, light weight model 3800 series oscilloscope has a wide frequency

range of operation and offers many features;

Wide operating frequency range:3806:DC-60MHz, 3804:DC-40MHz,3802:DC-

25MHz

High sensitivity: 1mV/div

Large size CRT: Large 6 inch CRT with internal graticule scale, hence easy to read

waveforms.

Scale: Parallax-free waveforms due to CRT‘s internal graticule scale.

Alt Mag: (x1) normal and (x10-3806) and (x5-3804/3802) magnification and

simultaneous display ability.

Alt Trig: Stabilized triggering can be achieved even with two unrelated signals.

TV synchronization: Stable TV signals can be displayed with the help of additional

circuitry.


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Auto focus: Focus deviation is automatically corrected.

Trigger Lock: Automatic synchronic state of the trigger circuit.

Component Tester (only for 3802 & 3804): Special circuit that tests the in & out

individual/components without any additional power requirement. It shows Faults,

component‘s value, characteristics of the component and even half dead

components.

FRONT PANEL DESCRIPTION

POWER SUPPLY & CRT

(1) POWER SWITCH ON/OFF

Verify line voltage; press power push-button to turn the power ON, if the

switch is released, the power is turned OFF.

(2) POWER LAMP

This lamp lights when the power is ON.

(3) INTENSITYKNOB

Turning this knob clockwise increases the brightness. Turn the knob fully

clockwise prior to connecting power.

(4) FOCUS KNOB


MCET Pathanamthitta

Adjusts the brightness to an appropriate level with the intensity control and

then adjust the focus control until the trace is at its clearest level. Although

automatic focus occurs, sometimes it may be slightly out and then readjust the

focus.

(5) TRACE ROTATION

This knob is used to correct the horizontal trace when it becomes slanted w.r.t

the horizontal scale, due to the effect of magnetic forces.

(6) SCALE ILLUM KNOB

This is used to adjust scale brightness. If turned clockwise, brightness gets

increased. This feature is useful for operations in dark locations/ while taking

pictures.

(38)AC RECEPTACLE (Rear panel)

This is the connector for AC power cable.

VERTICAL AXIS SECTION

(30)CH 1 INPUT CONNECTOR

A BNC connector is used for vertical input. Signal applied to this connector

becomes the Y-signal in X-Y mode.

(24)CH 2 INPUT CONNECTOR

Same as above except that the signal applied becomes the X-signal in X-Y

mode.

(22)(29) AC-GND-DC SWITCH

It selects the coupling method of the vertical amplifier.

AC: The vertical input is connected through a capacitor and hence the DC

component of the signal gets blocked and only AC component gets displayed.

GND: Input of the vertical amplifier gets grounded.

DC: Direct coupling takes place. Input signal including DC component gets

displayed on the CRT.

(25) (33) Volts/Div SELECTOR SWITCH

It‘s a step attenuator switch used to vary the vertical deflection sensitivity. It

can be set to a position which displays the input signal at the most convenient

height on the CRT. If a 10:1 probe is used, 10 times the height is calculated.


MCET Pathanamthitta

(26) (32) Var KNOB

This fine adjustment is used for varying the vertical axis deflection

continuously. On complete counter clockwise turning the sensitivity gets reduced

to <1/2.5 of the

VOLTS/DIV switch setting. Normally kept in full clockwise position. This knob is

mainly used for comparing two waveforms and rise time measurements.

(20) (36) x5 MAG BUTTONS

On pressing this button, the vertical axis gain gets 5 times magnified and the

maximum sensitivity of 1mV/div can be achieved.

(23) (35) POSITION

Used for moving CH1/ CH 2 trace up/ down on the CRT screen.

(21) INVERT PUSH BUTTON SWITCH

On pressing this switch the polarity of the input in CH 2 gets inverted. This

function is useful in comparing two waveforms of different polarities, displaying

the CH 1 & CH 2 difference waveforms using ADD. Vertical mode push buttons

are used for selecting vertical axis operating mode.

(34) CH 1

Signal applied to CH 1 gets displayed on the CRT screen.

(28) CH 2

Signal applied to CH 2 gets displayed on the CRT screen.

(34) (28) DUAL

When both CH1 & CH 2 buttons are pressed, the signals applied to CH 1 &

CH 2 gets displayed simultaneously on the CRT in either chopped/ alternate display.

(31) ADD

Displays the algebraic sum of CH 1 & CH 2 input voltages. The difference

value can be displayed on pressing the CH 2 invert button.

(40) CH 1 SIGNAL O/P CONNECTOR

It provides a 20mV/Div replica of CH 1 input which can be used with a

frequency counter.

HORIZONTAL AXIS SECTION

(15) Time/Div SELECTOR SWITCH


MCET Pathanamthitta

It selects the sweep speed from 0.1µs/div to 0.2s/div in 20 calibrated steps.

(11) X-Y

Displays the CH 1 & CH 2 inputs as an X, Y graph. Vertical deflection

corresponds to CH 1 i/p & horizontal deflection corresponds to CH 2 i/p. The

vertical position control (23) and Horizontal position control(14) positions the X,Y

display vertically and horizontally on CRT.

(12) SWEEP Var SWITCH

On turning all the way clockwise Time/Div switch indicates the sweep and

on all the way counterclockwise turning sweep indicates <1/2.5 the Time/Div

setting.

(14) HORIZONTAL POSITION

Moves the trace horizontally. Used for measuring the waveform‘s time

duration.

(9) x5/x10 PUSH BUTTON

On pressing, magnifies the trace by a factor of x5/x10. The sweep time

becomes 1/10 or 1/5 of the value indicated on the Time/Div switch. For

magnifying a portion of interest, move the portion of interest to the center graticule

and the press the switch.

(8) ALT MAG KNOB

Displays the normal and magnified trace simultaneously on the CRT.

TRIGGERING

(18) TRIGGER SOURCE SELECTOR SWITCH

Used for selecting the sweep trigger signal source;

Int: Input to CH 1/ CH 2 becomes the trigger signal.

CH 2: Input to CH 2 becomes the trigger signal.

Line: Power line frequency becomes the trigger source.

Ext: external signal connected to TRIG input acts as trigger.

(19) Ext INPUT CONNECTOR

It‘s the input terminal for external trigger signal.

(17) TRIG LEVEL KNOB

This control sets the amplitude point on the trigger waveform that starts the

sweep.

(10) SLOPE KNOB


MCET Pathanamthitta

Selects the polarity of the slope of the trigger source waveform. To select

(+) slope button is pushed out and for (-) slope button is pushed in.

(16)TRIG MODE SWITCH

Auto: Runs in auto sweep mode. A trace will be displayed in absence of

input signal. On proper triggered condition a stationery waveform is displayed.

Norm: A trace is displayed only on proper triggered condition or in

presence of input signal. Normal sweep is used when the input signal‘s frequency

is less than 25Hz.

TV-H: Effective on setting TV trig mode. Used for synchronizing

horizontal of TV signal.

TV-V: Effective on setting TV trig mode. Used for vertical synchronizing

of TV signal.

(39) Z-AXIS INPUT CONNECTOR

Used for intensity modulating the CRT screen. Since this is an integrated

DC system, (+) signal reduces brightness and (-) signal increases brightness.

(7) Cal 0.5V TERMINAL

outputs a 0.5Vpp 1 KHz rectangular wave for calibrating probes.

(27) GND TERMINAL

It acts as the grounding terminal.

(40) COMP. TEST

Used to change from oscilloscope to component tester. Also X-Y switch

(11) must be pushed and AC-GND-DC switches (22) (29) should be switched to

GND position.

(42) COMPONENT TEST IN

Terminals to which components or lead wires connecting components

under test are connected.

SIGNAL CONNECTION

We make use of probes for measuring high frequency signals since the input signals

are reduced to 1/10 of their value, this is unsuitable in case of low signals. For

measurement accuracy the probe has to be calibrated.

MEASURING PROCEDURES


MCET Pathanamthitta

Measuring DC Voltage

Set the AC-GND-DC switch to GND, and position the zero level to convenient

position on the screen. Set Volts/Div to appropriate setting and then set AC-GND-DC to

DC. Then a straight line trace gets deflected. The DC voltage can be obtained by

multiplying the amount of divisions the line deflects by the Volts/Div value.

Measuring AC Voltage

Follow the same procedure as above except change the AC-GND-DC switch position

to AC position.

Frequency and Time Measurement

Calculate the divisions on the screen between two adjacent +/- peaks of the displayed

waveform. Then multiply the value with the sweep time value obtained from the position

of Time/Div knob.

Time Difference Measurement

The following procedures are followed;

A To find the time CH 2 is delayed w.r.t CH 1 set the trigger signal source to Int.

B To find the time CH 1 is delayed w.r.t CH 2 set the trigger signal source to CH 2.

C Delay time = (No. of divisions from the rising edge of the trigger source to rising

edge of delayed signal)*Time/Div setting.

Component Test

Push X-Y switch for X-Y mode and set both AC-GND-DC switches to GND position

as well as set the VOLTS/DIV knob of CH 1 to 5V/DIV, CH2 to 2V/DIV, then push the

COMP. TEST switch. Components can be directly hooked to the COMP.TEST IN

terminals or through lead wires.

Function Generator(FG)

It is a very useful instrument for every test requirement. This is very convenient for

quick operation with minimum effort in instrument setting. It can be used to test the

frequency response of amplifiers, attenuators, filters, tec. The DC offset facility is very

much useful whenever it is required to provide some biasing while coupling the signal.

APLAB 2011A

Device Features:


MCET Pathanamthitta

Frequency Range : 1Hz- 2MHz in 6 decade ranges.

Output waveforms : Sine, triangle, balanced square, +ve square, -ve square,

variable

duty cycle pulse & variable slope ramp.

Sine Distortion : <3%

Attenuation : 0 dB, 20 dB, 40 dB, 60 dB

Pulse duty cycle : 10%-90% variable

Frequency counter range: 10Hz – 2MHz

D.C Offset : ±7.5V±5%, ±3.75V±5%


(1) EXT IN : This is a BNC receptacle for external input signal.

(2) MODE : This switch selects the frequency display mode.

(3) DISPLAY : This 4 digit 7 segment display indicates the frequency of selected

signal.

(4) LEDs : These LEDs indicate the frequency unit (Hz, KHz, & MHz)

(5) GATE LED : This LED glows during measurement.

(6) RANGE : Selects one of the six frequency ranges & corresponding range‘s

LED

glows.

(7) FUNCTION : The output waveform is selected by this switch & corr. LED

glows.

(8) DC OFFSET : This is a two position switch. In ON condition, it offsets the

selected

waveform in conjunction with the variable control.

(9) SYMMETRY : This is a two position switch. In ON condition, the duty cycle of

the


MCET Pathanamthitta

selected waveform can be varied by symmetry control.

(10) FREQUENCY: This is continuously variable frequency control coarse & fine.

(11) LEVEL : This is a continuously variable level control

(12) ATTENUATOR : This is a 4 position rotary switch and attenuates o/p by 20, 40 &

60dB.

(13) OUTPUT : This is a BNC connector for function output.

SCIENTECH 10 MHz Generator

Device Features:

Frequency Range : 1Hz- 10MHz (Sinewave).

1Hz-2MHz (all other signals)

Output waveforms : Sine, Square, Triangle, Ramp, Pulse.

Sine Distortion : 1.5%(2MHz), 2% (10MHz)

Attenuation : -20 dB, -40dB

Pulse duty cycle : 15%-85% variable

D.C Offset : ±5V adjustable.

Modulation : AM Standard, AM Balance, FM, ASK, FSK &

PWM.


(1) POWER : Push button switch to supply power to the instrument.

(2) DISPLAY : Digital 7 segment LED displays the 4-digit frequency output.

(3) FREQUENCY : 7 position push button switch, selects frequency from

10Hz-10MHz.

(4) FUNCTION : 5 position push button switch, selects desired function output.

(5) MODULATION I : 5 position push button switch, selects the modulation.

(6) MODULATION II: 4 position push button switch, selects the type of modulation.


MCET Pathanamthitta

(7) OUTPUT : BNC connector terminal for taking output from function

generator.

(8) SWEEP RATE : It is used to vary internal sweep.

(9) DUTY CYCLE : Used if pulse function is selected. Varies from 15% - 85%.

(10) FREQ. VAR : Varies the output frequency in conjunction with (3).

(11) AMPLITUDE Var: Helps to vary the output level in conjunction to attenuators.

(12) DC OFFSET : This control provides DC offset. An approx. of ±5V DC

can be superimposed. In case if DC offset is not required keep it OFF.

(13) ATTENUATOR: A combination of 20dB & 40dB is available. Pressing both at

same provides an attenuation of 60dB.

(14) MODULATION IN FOR MODULATION I: This BNC terminal is provided for

feeding modulating signal. Maximum input level is limited to 2Vpp.

(15) MODULATION IN FOR MODULATION II: This BNC terminal is provided for

feeding modulating signal. Maximum input level is limited to 2Vpp.

Digital Multimeter (DMM)

A multimeter or a multitester, is known as a VOM (Volt-Ohm meter). It is

an electronic measuring instrument that combines several measurement functions in one

unit. A typical multimeter includes features such as the ability to

measure voltage, current and resistance. Multimeters are of two types; Analog multimeters

(AMM) and Digital multimeters (DMM /DVOM.) Analog multimeters are usually based

on a microammeter whose pointer moves over a scale calibration for all the different

measurements that can be made while digital multimeters usually display digits, with

display bar of a length proportional to the quantity measured.

A multimeter can be a hand-held device useful for basic fault finding and field

service work or a bench instrument which can measure with a very high degree of

accuracy. They can be used to troubleshoot electrical problems in a wide array of industrial

and household devices such as electronic equipment, motor controls, domestic

appliances, power supplies, and wiring systems. Since, nowadays we deal with DMM

commonly, a brief description on a commonly used DMM and its functions are described

below;

http://en.wikipedia.org/wiki/Electronics

http://en.wikipedia.org/wiki/Measuring_instrument

http://en.wikipedia.org/wiki/Voltage

http://en.wikipedia.org/wiki/Electric_current

http://en.wikipedia.org/wiki/Electrical_resistance

http://en.wikipedia.org/wiki/Microammeter

http://en.wikipedia.org/wiki/Calibrated

http://en.wikipedia.org/wiki/Fault

http://en.wikipedia.org/w/index.php?title=Bench_instrument&action=edit&redlink=1

http://en.wikipedia.org/wiki/Electronic_equipment

http://en.wikipedia.org/wiki/Domestic_appliance



http://en.wikipedia.org/wiki/Power_supply


MCET Pathanamthitta

MECO Model:603

Device Features:

Display · 3 ½ digit liquid crystal display (LCD) with

a maximum reading of 1999.

Polarity · Automatic, (-) negative polarity indication.

Zero adjustment · Automatic

Over range indication · Highest digit of(1) or (-1) is displayed at

MSD

Low battery · ―(B)‖ is displayed when the battery voltage

drops below the operating voltage

Measurement rate · 3 measurements per second, nominal

Operating conditions · 0°C to + 50°C at < 75% RH

Storage conditions · -20°C to + 60°C, 0-80% RH with battery

removed.

Accuracy · Accuracy specifications at 23 ± 5°C, less than 75% RH

Power Supply · Single, standard 9-volt battery.

Battery life (typical) · 200 hours.

1.2 ELECTRICAL SPECIFICATIONS

Accuracies are ± (% reading plus number of digits) at 23 ± 5°C, and humidity of

less than 75% RH.

DC VOLTAGE

Ranges : 200mV, 2V, 20V, 200V, 1000V

Accuracy : ±(0.5%rdg + 1dgt) on all ranges

Resolution : 100µV to 1V

Input Impedance : 10MV

Overload Protection : 500V DC/350VAC for 15 sec. on 200mV range,

1200V DC/800V AC on all other ranges.

AC VOLTAGE (50-500Hz)

Ranges : 200mV, 2V, 20V, 200V, 750V

Accuracy : ± (1% rdg + 4 dgt) on all ranges except

±(1.5% rdg + 4 dgt) on 750V


MCET Pathanamthitta

Resolution : 100µV to 1V

Input Impedance : 10MΩ

Overload Protection : 500V DC/350VAC for 15 sec. on 200mVrange, 1200V

DC/800V AC on all other ranges.

DC CURRENT

Ranges : 200mA, 2mA, 20mA, 200mA, 20A (In 20A range maximum

measuring time ≤ 30s with an interval of 5 minutes)

Accuracy : ± (1% rdg + 1 dgt) on all ranges except ±(2% rdg + 3 dgt) on

20A range

Resolution : 100nA to 10mA

Voltage Burden : 325mV except, 1.4V max. on 20A range

Overload Protection : 0.8A/250V FUSED. on all ranges except 24A unfused for 30

sec. on 20A range

AC CURRENT (50-500Hz)

Ranges : 200mA, 2mA, 20mA, 200mA, 20A (In 20A range maximum

measuring time ≤ 30s with an interval of 5 minutes)

Accuracy : ± (1.2% rdg + 4 dgt) on all ranges except ±(2% rdg +4 dgt) on

20A range

Resolution : 100nA to 10mA

Voltage Burden : 325mV except, 1.4V max. on 20A range

Overload Protection : 0.8A/250V FUSED on all ranges except 24A unfused for 30

sec. on 20A range

RESISTANCE

Ranges : 200Ω, 2KΩ, 20KΩ, 200KΩ, 2000KΩ, 20MΩ, 200MΩ

Accuracy : ± (0.8% rdg + 1dgt) on all ranges except

± (1% rdg + 3 dgt) on 200Ω

± (3% rdg + 3 dgt) on 20MΩ

± (5% rdg + 10 dgt) on 200MΩ

Resolution : 100mΩ to 100KΩ

Overload Protection : 500V DC/AC

Test Voltage : 200Ω, 200MΩ; 3.2V max; other ranges 0.3V max.


MCET Pathanamthitta

CONTINUITY BEEPER

Threshold : 100V approx.

Response Time : 100mS

hFE TEST

Base DC Current : 10 mA

VCE : 2.8 ± 0.4V

Range : 0 To 1000

DIODE TEST

Test Current : 1.0 ± 0.6Ma

Test Voltage : 3.2V max.

MEASURING PROCEDURES

Voltage Measurement

1. Connect red test lead to ―V-Ω‖ input terminal and black test lead to ―COM‖ input

terminal.

2. Set Function/Range switch to desired voltage type (DC or AC) and range. If magnitude

of voltage is not known, set switch to the highest range and reduce until a satisfactory

reading is obtained.

3. Turn off power to the device or circuit being tested and discharge all capacitors.

4. Connect test leads to the device or circuit being measured.

5. Turn on power to the device or circuit being measured. Voltage value will appear on the

digital display along with the voltage polarity.

6. Turn off power to the device or circuit being tested and discharge all capacitors prior to

disconnecting test leads.

Current Measurement

1. Connect red test lead to the ―mA‖ input terminal for current measurements up to

200mA. Connect black lead to the COM input terminal.

2. Set Function/Range switch to desired current type (DC or AC) and range. If magnitude

of current is not known, set switch to the highest range and reduce until a satisfactory

reading is obtained.

3. Turn off power to the device or circuit being tested and discharge all capacitors.


MCET Pathanamthitta

4. Open the circuit in which current is to be measured. Now securely connect test leads in

series with the load in which current is to be measured.

5. Turn on power to the device or circuit being tested.

6. Read current value on digital display.

7. Turn off all power to the device or circuit being tested and discharge all capacitors.

8. Disconnect test leads from circuit and reconnect circuit that was being tested.

9. For current measurement of 200mA or greater, connect the red test lead to ―20 A‖ input

terminal & black test lest lead to the ―COM‖ input terminal. If the resistance being

measured is part of a circuit, turn off power to the circuit and discharge all capacitors.

Resistance Measurements

1. Connect red test lead to V-Ω input terminal and black test lead to COM input terminal.

2. Set Function/Range switch to desired V position. If magnitude of resistance is not

known, set the switch to highest range and reduce until a satisfactory reading is obtained.

3. If the resistance being measured is part of a circuit, turn off power to the circuit and

discharge all capacitors.

4. Connect test leads to the device or circuit being measured. When measuring high

resistance, be sure not to contact adjacent points even if insulated, because some insulators

have a relatively low insulation resistance, causing the measured resistance to be lower

than the actual resistance.

5. Read resistance value on digital display. If a high resistance value is shunted by a large

value of capacitance, allow digits to stabilize.

Diode Tests

1. Connect red test lead to V-Ω input terminal and black test lead to COM input terminal.

2. Set Function/Range switch to the diode test position.

3. If the semiconductor junction being measured is part of to a circuit, turn off power to

the circuit and discharge all capacitors.

4. Connect test leads to the device.

5. Read forward voltage drop value on digital display.

6. If the digital display reads over range (1) reverse the lead connections. The placement of

the test leads when the forward reading is displayed indicates the orientation of the diode.

The red lead is positive and the black lead is negative. if over range (1) is displayed with

both lead connections, the junction is open. If a low-reading (less than 1,000) is obtained

with both lead connections, the junction is shorted internally or (if junction is measured in


MCET Pathanamthitta

a circuit) the junction is shunted by a resistance less than 1KV. In the latter case the

junction must be disconnected from the circuit in order to verify its operation.

Transistor Junction Tests

1. Bipolar transistors can be tested in the same manner as diode, junctions formed between

the base and emitter and the base and collector of the transistor. Measurement between the

collector and emitter also should be made to determine if a short is present.

Transistor hFE Measurements

1. Transistor must be out of circuit. Set the function/range switch to the hFE position.

2. Plug the emitter, base and collector leads of the transistor into the correct holes in either

the NPN or the PNP transistor test socket, whichever is appropriate for the transistor being

checked. Read the hFE (beta, or DC current gain) in the display.

Continuity Measurements

1. Set the selectors switch to the ))) position.

2. Continuity between probe tips will be indicated by an audible beep when resistance is

below 100Ω.

TROUBLESHOOTING

If there appears to be a malfunction during the operation of the meter, the following steps

should be performed in order to isolate the cause of the problem:

1. Check the battery.

2. Review the operating instructions for possible mistakes in operating procedure.

3. Inspect and test the Test Probes for a broken or intermittent connection.

4. Inspect and test the fuse. If it is necessary to replace the fuse, be sure to install one of

the proper current ratings.

DC-Power supply

The standard power supply you will use for most of your experiments is the

―power brick‖ sitting on your desk. This power supply is plugged into the connector on the

breadboard platform. The wires coming out of the back end of the breadboard connector

are shown in Figure . GROUND is a direct connection to the Earth through the ground

terminal on the three-prong wall plug. COM stands for Common Ground. It is the

reference point from which the other voltages (+5V, ±12V) are measured. COM is a

―floating‖ reference point. ―Floating‖ means it is not connected to Earth ground. All four

terminals (+5V, ±12V, and COM) are isolated by a transformer, whose secondary


MCET Pathanamthitta

windings power the circuitry that generates the output voltages. In fact, COM can be

biased by a different power supply to any potential (up to 30V or so) and the three output

voltages will likewise follow. The key thing to note is that the output voltages are relative

to the floating COM terminal and not to the GND terminal. Thus, for all the labs it is

recommended to connect the COM terminal to the GND terminal to ensure that all supply

voltages generated by the ―power brick‖ are referenced to GND. Each voltage from the

DC power brick (+5V, ±12V) is sent through a separate fuse on the breadboard mount.

Make sure you only make connections to the supply voltage after the fuse. In the case of a

wiring error, the fuse will blow, thus saving the power supply from possible damage. We

do not provide an unlimited supply of replacement fuses. Please check your circuits very

carefully before connecting to power!

DC-Power supply

Tunable voltage/current source

The HP E3616A is a tunable voltage or current source.There are two knobs:

Voltage and Current. These are used to adjust the constant voltage output by the device or

the constant current output by the device. There are little green LEDs (CV and CC) near

the display which indicate if the power supply is voltage or current limited, if it operates in

voltage or current mode. For constant voltage mode, the current knob must be turned to a

setting above any that need be supplied and then the voltage knob is set for the desired

voltage. For constant current mode, the voltage knob must be turned to a setting above any

that need be supplied and then the current knob is set for the desired current. The potential

at the red terminal is always above that at the black terminal by the amount shown on the

readout, but this potential difference is, like the power pack, floating. If the black terminal

is wired to the green ground the red terminal will be at the potential given on the readout.

If the red terminal is wired to the ground, the black terminal will be at a potential equal to

the negative of the readout. The supplies may already have the black terminal grounded


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(with an easy to miss wire between them) for using the red terminal as a positive supply

voltage.

Tunable voltage/current supply, also called the HP power supply.

Soldering Iron

A soldering iron is a hand tool used in soldering. It supplies heat to melt solder so that

it can flow into the joint between two workpieces. A soldering iron is composed of a

heated metal tip and an insulated handle. Heating is often achieved electrically, by passing

an electric current (supplied through an electrical cord or battery cables) through a

resistive heating element. Cordless irons can be heated by combustion of gas stored in a

small tank, often using a catalytic heater rather than a flame. Simple irons less commonly

used than in the past were simply a large copper bit on a handle, heated in a flame.

Soldering irons are most often used for installation, repairs, and limited production work

in electronics assembly. High-volume production lines use other soldering methods. Large

irons may be used for soldering joints in sheet metal objects. Less common uses include

pyrography (burning designs into wood) and plastic welding.

Electric soldering iron

De soldering pump

A de soldering pump, colloquially known as a solder sucker, is a manually-

operated device which is used to remove solder from a printed circuit board. There are two

types: the plunger style and bulbstyle. (An electrically-operated pump for this purpose

would usually be called a vacuum pump.) The plunger type has a cylinder with a spring-

loaded piston which is pushed down and locks into place. When triggered by pressing a

button, the piston springs up, creating suction that sucks the solder off the soldered

https://en.wikipedia.org/wiki/Hand_tool

https://en.wikipedia.org/wiki/Soldering

https://en.wikipedia.org/wiki/Solder

https://en.wikipedia.org/wiki/Heating_element

https://en.wikipedia.org/wiki/Catalytic_heater

https://en.wikipedia.org/wiki/Pyrography

https://en.wikipedia.org/wiki/Plastic_welding

https://en.wikipedia.org/wiki/Printed_circuit_board

https://en.wikipedia.org/wiki/Vacuum_pump

https://en.wikipedia.org/wiki/Spring_(device)

https://en.wikipedia.org/wiki/Piston


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connection. The bulb type creates suction by squeezing and releasing a rubber bulb. The

pump is applied to a heated solder connection, then operated to suck the solder away.

A typical spring-loaded solder sucker

Soldering and De soldering stations

A soldering station, invariably temperature-controlled, consists of an electrical power

supply, control circuitry with provision for user adjustment of temperature and display,

and a soldering iron or soldering head with a tip temperature sensor. The station will

normally have a stand for the hot iron when not in use, and a wet sponge for cleaning. It is

most commonly used for soldering electronic components. Other functions may be

combined; for example a rework station, mainly for surface-mount components may have

a hot air gun, vacuum pickup tool, and a soldering head; a de-soldering station will have a

de-soldering head with vacuum pump for de-solderingthrough hole components, and a

soldering iron head.

Temperature-controlled soldering station

Pliers

Pliers arehand tools used to hold objects firmly, possibly developed from tongs used

to handle hot metal in Bronze Age Europe. They are also useful

for bending and compressing a wide range of materials.

Flat-nose pliers

Wire stripper

A simple manual wire stripper is a pair of opposing blades much like scissors or wire

cutters. The addition of a center notch makes it easier to cut the insulation without cutting

the wire. This type of wire stripper is used by rotating it around the insulation while

https://en.wikipedia.org/wiki/Rework_station

https://en.wikipedia.org/wiki/Surface-mount_device

https://en.wikipedia.org/wiki/Hot_air_gun

https://en.wikipedia.org/wiki/Through-hole

https://en.wikipedia.org/wiki/Hand_tool

https://en.wikipedia.org/wiki/Tongs

https://en.wikipedia.org/wiki/Bronze_Age

https://en.wikipedia.org/wiki/Bending

https://en.wikipedia.org/wiki/Compression_(physical)

https://en.wikipedia.org/wiki/Scissors

https://en.wikipedia.org/wiki/Wire_cutters




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applying pressure in order to make a cut around the insulation. Since the insulation is not

bonded to the wire, it then pulls easily off the end.

A wire stripper

Screw driver

A screwdriver is a tool, manual or powered, for turning (driving or removing) screws.

A typical simple screwdriver has a handle and a shaft, and a tip that the user inserts into

the screw head to turn it. The shaft is usually made of tough steel to resist bending or

twisting.

Tweezers

Tweezers are tools used for picking up objects too small to be easily handled with

the human hands.Most of the electronic grade tweezers are coated with a colored epoxy

resin which is insulating, shock resistant and provides better grip.

Crimping tool

A crimping tool is a device used to conjoin two pieces of metal by deforming one or

both of them in a way that causes them to hold each other. The result of the tool's work is

called a crimp. A good example of crimping is the process of affixing a connector to the

end of a cable.

https://en.wikipedia.org/wiki/Tool

https://en.wikipedia.org/wiki/Screw

https://en.wikipedia.org/wiki/Human_hand


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EXPERIMENT NO:4

TESTING OF ELECTRONIC COMPONENTS

AIM

To familiar with the testing of following Electronic components using multimeter.

Resistor

Capacitor

Diode

Transistor

UJT

JFET

THEORY

To test resistor with multimeters

To check the value of a resistor, it should be removed from the circuit. The

surrounding components can affect the reading and make it lower.

To test capacitor with the Digital Multimeter

1. Make sure the capacitor is discharged.

2. Set the meter on Ohm range (Set it at lease 1000Ohm = 1k).

3. Connect the Meter leads to the Capacitor terminals.

4. Digital meter will show some numbers for a second. Note the reading.

5.And then immediately it will return to the OL (Open Line). Every attempt of Step 2 will

show the same result as was in step 4 and Step 5. It‘s mean that Capacitor is in Good

Condition.


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6. If there is no Change, then Capacitor is dead.

To test the diode

Digital multimeters can test diodes using one of two methods:

1. Diode Test mode: almost always the best approach.

2. Resistance mode: typically used only if a multimeter is not equipped with a Diode Test

mode.

Things to know about the Resistance mode when testing diodes:

Does not always indicate whether a diode is good or bad.

Should not be taken when a diode is connected in a circuit since it can produce a

false reading.

CAN be used to verify a diode is bad in a specific application after a Diode Test

indicates a diode is bad.

A diode is best tested by measuring the voltage drop across the diode when it is forward-

biased. A forward-biased diode acts as a closed switch, permitting current to flow.

Amultimeter‘s Diode Test mode produces a small voltage between test leads. The

multimeter then displays the voltage drop when the test leads are connected across a diode

when forward-biased. The Diode Test procedure is conducted as follows:


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1. Make certain a) all power to the circuit is OFF and b) no voltage exists at the diode.

Voltage may be present in the circuit due to charged capacitors. If so, the capacitors

need to be discharged. Set the multimeter to measure ac or dc voltage as required.

2. Turn the dial (rotary switch) to Diode Test mode ( ). It may share a space on the

dial with another function.

3. Connect the test leads to the diode. Record the measurement displayed.

4. Reverse the test leads. Record the measurement displayed.

The diode is REVERSE BIASED in the The diode is FORWARD BIASED in the

diagram above and diodes not conduct. diagram above and it conducts

To test the transistor

a) Testing an NPN Transistor.

Place the three legs of the Transistor first in the E-B-C formation. The multimeter will

show the reading if this formation is correct, else it will show over range.


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If the previous method doesn‘t work, place the three legs of the Transistor in the B-C-E

formation. If multimeter shows reading then it‘s correct. The reading is nothing but thr

HFE of that transistor.

b) Testing PNP Transistor.

Place the three legs of the transistor in the same manner as discussed above.

After placing the transistor in the correct formation, multimeter would show the HFEvalue

of the transistor.

To test UJT

UJT (Uni- junction transistor) can be easily tested by using a digital

multimeter.The three steps for testing the health of a UJT are as follows.


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1.Measuring the resistance between B1 and B2 terminals.

Set your digital multimeter in resistance mode.Connect the positive lead of

multimeter to the B1 terminal and negative lead to the B2 terminal.The multimeter will

show a high resistance( around 4 to 10K ). Now connect the positive lead to B2 terminal

and negative lead to B1 terminal.Again the multimeter will show a high resistance (around

4 to 10K ).Also both the readings will be almost same.

3. Reverse biasing the emitter junction.

Set the digital multimeter in resistance mode. Connect negative lead of the multimeter to

the emitter and positive lead to the B1.The multimeter will show a high resistance (around

100‘s of K‘s).Now connect the negative lead once again to the emitter and positive lead to

B2.Again the meter will show a high resistance. In both cases the reading will be almost

same. This test is almost like reverse biasing a diode.

3. Forward biasing the emitter junction.


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Set the digital multimeter in resistance mode. Connect the positive lead to the emitter and

negative lead to B1.The multimeter will show a low resistance (around few 100

ohms).Now connect the positive lead once again to the emitter and negative lead to the B2

terminal. Again the multimeter will show a low resistance reading (around few 100

ohms).In both cases the reading will be almost same. This test is almost like forward

biasing a diode.

To test JFET

JFET can be seen as an NPN-type transistor, the gate G corresponds to the base b, the

corresponding collector drain D c, S corresponds to the source emitter e. So as long as the

measurement as measured transistor PN junction, the reverse resistor. The multimeter dial

in the R 100 block, with black pen then one of FET electrodes, then the red pen are the

other two poles, when there were two low resistance, the black pen then is the FET gate,

the red pen then is the drain or source. Of the JFET, the drain and 105 datasheet and

source are interchangeable. For 4-pin JFET, the other pole is shielded pole (using the

ground). Testing a JFET with a multimeter might seem to be a relatively easy task, seeing

as how it has only one PN junction to test: either measured between gate and source, or

between gate and drain.


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Testing continuity through the drain-source channel is another matter, though. Remember

from the last section how a stored charge across the capacitance of the gate-channel PN

junction could hold the JFET in a pinched-off state without any external voltage being

applied across it? This can occur even when you‘re holding the JFET in your hand to test

it! Consequently, any meter reading of continuity through that channel will be

unpredictable, since you don‘t necessarily know if a charge is being stored by the gate-

channel junction. Of course, if you know beforehand which terminals on the device are the

gate, source, and drain, you may connect a jumper wire between gate and source to

eliminate any stored charge and then proceed to test source-drain continuity with no

problem. However, if you don’t know which terminals are which, the unpredictability of

the source-drain connection may confuse your determination of terminal identity.

A good strategy to follow when testing a JFET is to insert the pins of the transistor into

anti-static foam (the material used to ship and store static-sensitive electronic components)

just prior to testing. The conductivity of the foam will make a resistive connection

between all terminals of the transistor when it is inserted. This connection will ensure that


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all residual voltage built up across the gate-channel PN junction will be neutralized, thus

―opening up‖ the channel for an accurate meter test of source-to-drain continuity.

Since the JFET channel is a single, uninterrupted piece of semiconductor material, there

is usually no difference between the source and drain terminals. A resistance check from

source to drain should yield the same value as a check from drain to source. This

resistance should be relatively low (a few hundred ohms at most) when the gate-source

PN junction voltage is zero. By applying a reverse-bias voltage between gate and

source, pinch-off of the channel should be apparent by an increased resistance reading

on the meter.

For n-channel JFET

1. Switch your multimeter to the "Diode Test" position.

2. Hold the positive lead to the JFET's gate terminal.

3. Hold the negative lead to the JFET's source terminal. The multimeter should show

a p–n junction forward voltage drop ~ 650-750 mV.

4. Hold the negative lead to the JFET's drain terminal. The multimeter should show a

p–n junction forward voltage drop ~ 650-750 mV.

5. Hold the positive lead to the JFET's source terminal. The multimeter should show a

low voltage drop - the JFET is ON.

6. Hold the negative lead to the JFET's gate terminal. The multimeter should show a

p–n junction reverse voltage drop - overrange.

7. Hold the negative lead to the JFET's gate terminal. Connect the JFET's drain

terminal to the JFET's gate terminal. The multimeter should show aoverrange - the

JFET is OFF.


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EXPERIMENT NO:5

INTERCONECTION METHODS AND SOLDERING PRACTICE

AIM

To familiarize interconnection methods and soldering practice

COMPONENTS REQUIRED

Master Appliance Soldering Iron

Knife/blade

Solder

Damp Sponge

Flux to remove oxides

THEORY

Breadboard

A breadboard is a construction base for prototyping of electronics. Originally it

was literally a bread board, a polished piece of wood used for slicing bread. In the 1970s

the solder less breadboard became available and nowadays the term "breadboard" is

commonly used to refer to these. "Breadboard" is also a synonym for "prototype".Because

the solder less breadboard does not require soldering, it is reusable. This makes it easy to

use for creating temporary prototypes and experimenting with circuit design. For this

reason, solder less breadboards are also extremely popular with students and in

technological education. Breadboards are one of the most fundamental pieces when

learning how to build circuits. Wire wrap is a process that involves wrapping wires

around conductive posts attached to a perf board (a.k.a. a proto board). Another common

use of breadboards is testing out new parts, such as Integrated circuits (ICs). When you are

trying to figure out how a part works and constantly rewiring things, you don‘t want to

have to solder your connections each time.

Soldering Iron

Master Appliance Soldering irons are exceptionally handy and indispensible tools.

Professionals and hobbyists alike use soldering irons in various industries and

applications. Most commonly, soldering irons are used in the electronic industry. Of

course, before you begin a project with your soldering iron, you should know how to use a

soldering iron properly and safely. Soldering accomplishes a strong bond between two

https://en.wikipedia.org/wiki/Prototype

https://en.wikipedia.org/wiki/Electronic_circuit

https://en.wikipedia.org/wiki/Prototype

https://en.wikipedia.org/wiki/Soldering

http://en.wikipedia.org/wiki/Perfboard

https://www.sparkfun.com/products/8619


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pieces of metal by joining them together. In this procedure, a material called solder, an

alloy mixture of tin and lead, flows over two pre-heated pieces of metal and holds them

together. The process is similar to welding but differs because when you weld you are

fusing and melting two pieces together to make one. When you solder you are essentially

‗gluing‘ two parts together with molten metal. Most metals with the exception of

aluminum, white metal and porous cast iron can be soldered. Below, you will find

instructions and illustrations that show you how to use a soldering iron.Solder is used for

joining two or more metals at temperatures below their melting points.The popularly used

solders are alloys of tin(60%)and lead(40%) that melts at 375ᶿF and solidifies when it

cools.

Types of soldering fluxes

Soldering fluxes can be classified as:

(a) Organic Fluxes :Organic fluxes are either rosin or water soluble materials. Rosin used

for fluxes are wood gum, and other rosin which are not water soluble. Organic fluxes

are mostly used for electrical and electronic circuit making. These are chemically

unstable at elevated temperature but non-corrosive at room temperature.

(b) Inorganic Fluxes: Inorganic fluxes are consists of inorganic acids; mixture of metal

chlorides (zinc and ammonium chlorides). These are used to achieve rapid and active

fluxing where formation of oxide films are problems. Fluxes should be removed after

soldering either by washing with water or by chemical Soldering and Brazing

solvents.

The main functions performed by fluxes are :

(a) Remove oxide films and tarnish from base part surfaces,

(b) Prevent oxidation during heating, and

(c) Promote wetting of the faying surfaces.

The fluxes should

(a) Be molten at soldering temperature

(b) Be readily displaced by the molten solder during the process, and

(c) Leave a residue that is non-corrosive and non-conductive.

De-soldering


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It is the removal of solder from previously soldered joint .Desolder pump is

commonly used device for this purpose .When the solder melts by the action of the

soldering iron ,a trigger on the desolder pump should be activated to create vaccum.This

vaccum pulls the solder into the tube.

Steps

1. Prepare a work space. Lay down a mat or piece of cardboard that will catch any

solder that you drip.

2. Warm your soldering iron. If your soldering iron is electric, you‘ll need to allow it to

warm up on its stand. If your soldering iron runs on butane, as Master Appliance soldering

irons do, fill it with gas holding the unit firmly with the refill nozzle pointed upwards and

press down. Gas will overflow from nozzle when tank is full.

3. Secure the items you are soldering. It helps to have an extra hand while you are

soldering. We suggest using a vise or frame to secure your work.

4. Clean your soldering iron. Because soldering irons get so hot, they oxidize and become

dirty quickly. They key to reliable connections is clean components so make sure that your

soldering tip and parts you are joining are clean. To accomplish this, pass the tip of your

soldering iron on a wet sponge until it shines

5. Apply flux. In soldering it often becomes necessary to use materials called fluxes to

help remove oxides and keep them absent while you solder. Flux needs to melt at a

temperature lower than solder so that it can do its job prior to the soldering action. There

are different methods to apply flux. The method you choose will be dependent on the

items you are soldering.

6. Tin your soldering iron. If you want to know everything there is to know about how to

use a soldering iron, you‘ll need to know how to tin. Tinning is the process of coating a

soldering tip with a thin coat of solder. Melt a thin layer of solder on your iron‘s tip. This

aids in heat transfer between the tip and the component you are soldering, and also gives

the solder a base from which to flow from. This process may need to be repeated as you

solder. You will only touch the tip of the soldering iron to the solder when you tin. Do not

touch the tip of the iron to the solder while you are actually soldering.


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7. Start soldering. Hold the soldering iron like you would a pen in the hand you write

with and the solder in the other.

8. Place the tip of the soldering iron tip. The tip needs to touch both the wire lead and

the surface so they achieve the same temperature.

9. Feed solder onto the joint after you have heated the area for two to three seconds.

Touch the solder to the side of the connection opposite the soldering iron. Then, let the

solder flow only until the connection is covered.

10. Remove the solder first. Then, remove the iron. Make sure the joint remains

stationary while it cools.

11. Evaluate. A smooth, shiny and volcano shaped joint is what you are looking for. If

this isn‘t what you see, you‘ll need to reheat and feed in more solder.

12. Remove leftover flux with a commercial flux cleaner.

Using a heat sink

There are some components (i.e transistors) that can be damaged by the heat that

soldering produces. If you are new to soldering, it‘s good idea to use a heat sink clipped to

the lead between the joint and the component‘s body. A cheaper alternative is a standard

crocodile clip

Warnings

DO NOT lay a soldering iron down on any surface. A soldering iron should either

be placed on a stand or sealed with a heat resistant cap after every use. Note:

Master Appliance's line of soldering irons is butane powered. All of our irons come

with heat protective caps.

Soldering should be completed in a well ventilated area.

Lead is present in most solders. Be sure to wash your hands after your project, or

better yet wear gloves.

The tip of a soldering iron is very hot. Contact with the tip of a soldering iron

would result in a nasty burn.


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Your soldering iron will perform better if kept clean. A damp sponge can be used

to clean residue caused by flux material. A very small skim of flux should be

applied to the iron after the cleaning.

Safety precautions in soldering.

Keep solder iron always on its stand.

All electrically operated instruments/equipment should have proper

earthing.

Sometimes emission of (smoke) soldering operation may be poisonous due

to a particular type of flux. Operator should have protection from the same.

Flux should be applied gradually while soldering.

While diluting HCl, water should not be added to HCl but HCl should be

mixed into the water drop by drop, to avoid accident.

Work place should have enough ventilation and smoking should be strictly

prohibited during the operation. Work place should have the facility of first

aid.

It should be noted down good quality surface preparation always

contributes to good quality joint.


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EXPERIMENT NO:6

PRINTED CIRCUIT BOARD

AIM

To familiarize with printed circuit board (PCB) design and fabricate a single sided

PCB with manual etching and drilling.

COMPONENTS REQUIRED

Copper clad sheet, a little paint, drilling machine and ferric chloride solution.

THEORY

Printed circuit board (PCB)

A printed circuit board, or PCB, is used to mechanically support and electrically

connect electronic components using conductive pathways, tracks or signal traces etched

from copper sheets laminated onto a non-conductive substrate. It is also referred to as

printed wiring board (PWB) or etched wiring board.A PCB populated with electronic

connectors and components is called a printed circuit assembly (PCA), printed circuit

board assembly or PCB Assembly (PCBA). The vast majority of PCBs are manufactured

with "1 ounce copper" on the outer layers. If there are inner layers, they are almost always

manufactured with "1/2 ounce copper".

Printed circuit board

The thickness of the copper layer on the PCB affects the behavior of the circuit.

PCB copper thickness is usually measured in ounces per square foot, or frequently, just

ounces. It can also be given in micrometers, inches or mils."Multi layer" printed circuit


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boards have trace layers inside the board. One way to make a 4-layer PCB is to use a two-

sided copper-clad laminate, etch the circuitry on both sides, then laminate to the top and

bottom prepreg and copper foil.

Types of Printed Circuit Boards

1) Single Sided Board

This is the least complex of the Printed Circuit Boards, since there is only a single

layer of substrate. All electrical parts and components are fixed on one side and copper

traces are on the other side.

2) Double Sided Board

This is the most common type of board, where parts and components are attached to

both sides of the substrate. In such cases, double-sided PCBs that have connecting traces

on both the sides are used. Double-sided Printed Circuit Boards usually use through-hole

construction for assembly of components.

3) Multi Layered Board

Multi layered PCB consists of several layers of substrate separated by insulation. Most

common multilayer boards are: 4 layers, 6 layers, 8 layers, and 10 layers. However, the

total number of layers that can be manufactured can exceed over 42 layers. These types of

boards are used in extremely complex electronic circuits.

Plated-Through Hole (PTH)

For PTH (plated-through holes), additional steps of electro less deposition are done

after the holes are drilled, then copper is electroplated to build up the thickness, the boards

are screened, and plated with metal. The metal becomes the resist leaving the bare copper

to be etched away.


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The picture above is a Plated-Through Hole in an ten layer board. The amount of

plating used in the hole depends on the number of layers in the printed circuit board,

however only the least amount of metal is used for this process. Holes through a PCB are

typically drilled with small-diameter drill bits made of solid coated tungsten carbide.


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EXPERIMENT NO:7

ASSEMBLING OF ELECTRONIC CIRCUIT/SYSTEM ON GENERAL PURPOSE PCB

1. Fixed voltage power supply with transformer, rectifier diode, capacitor and

zener/IC regulator

AIM:

To design and setup fixed voltage power supply with transformer, rectifier, diode,

capacitor filter, zener / IC regulator.

COMPONENTS REQUIRED

Diode – 1N4001, BZ 5.1

Capacitor − 470µF, .01µF

Function Generator

CRO

Miscellaneous – Probes, Connecting wires, Bread board, etc.

THEORY

Fixed voltage power supply circuit diagram using ic regulator.

5V regulated power supply schematic

This is a small +5V regulated power supply circuit. In that case here we used 7805

Voltage Regulator IC. 7805 is a +5 Volt regulator IC from 78xx chips family. The circuit


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has internal current limiting and thermal protection capacity. A 9V 2A steps down

transformer is used to covert 230V to 9V from mains. Here used a bridge rectifier made by

four 1N 4007 diode to convert AC-DC . 470uF 50v as C1 is used for filtering. This circuit

is very easy to build. For good performance recommended input voltage 8V-18V. If over

400mA current is needed at output then use a heat sink with the 7805 IC.

12V regulated power supply schematic

Here this circuit diagram is for +12V regulated (fixed voltage) DC power supply.

These power supply circuit diagram is ideal for an average current requirement of 1Amp.

This circuit is based on IC LM7812. It is a 3-terminal (+ve) voltage regulator IC. It has

short circuit protection, thermal overload protection. LM7812 IC is from LM78XX series.

The LM78XX series IC is positive voltage regulator IC for different voltage requirements,

for example LM7805 IC is made for 5 volt fixed output voltage. There is LM79XX IC

series for negative voltage.

http://www.circuitstune.com/2012/11/100-watt-inverter-circuit-12vdc-220vac.html

http://www.circuitstune.com/2012/09/7805-voltage-regulator-circuit-7805-pinout.html


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2 - LED blinking circuit using astable multivibrator with transistor BC107.

AIM:

To design and setup an LED blinking circuit using astable multivibrator with

transistor bc107.

COMPONENTS REQUIRED

Resistors– 470 Ohm

Potentiometer− 5 mm , red

Capacitor − 47 μF / 16V

Transistor − BC107

LED − 5 mm , red

THEORY

Circuit diagram

This is a simple flashing led circuit with 2 LEDs and 2 NPN transistors.It

illustrates the behavior of transistors and capacitors and if you use an oscilloscope it will

be very easy to determine what happens in this astablemultivibrator circuit. It‘s state is

constantly changing and this change affect the flow of current and voltage and the effect

will be visible with the two LEDs.The speed of the led flasher may be adjusted with

potentiometer P1. Being an astablemultivibrator, the circuit has no stable state but

oscillates continuously between the two states back and forth. The two transistors T1 and

T2 turn and lock each other by turn. The smaller the capacitor value is and the smaller the


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resistance, the appropriate LED goes out faster, for the benefit of other, who then

immediately turns on.

The activation time of T2 is t, a = 0.7 x R1 x C1,

The switch-off t off = 0.7 x R2 x C2.

The switch from T1 is t, a = 0.7 x R2 x C2, the off t off = 0.7 x R1 x C1.

It is recommended to always use the equivalent transistors. If one of the transistors is

defective, wrong or have a malfunction, so does this to the full functionality of this circuit.

One LED lights up and the other is dimmed.

The ―two flashing led‖ circuit is designed for 9 Volts but it works at lower voltages too. In

this design we used red leds but by changing the series resistors R1 and R4 you can also

use different LED colors


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3- Sine wave generation using ic741 op-amp

AIM:

To design and setup sine wave generation using ic741 opamp in IC base.

COMPONENTS REQUIRED

DC Source, CRO, Bread board, Op-amp, Potentiometer, Capacitors, Resistors, BFW10,

1N4007

THEORY

This is an audio frequency oscillator of high stability and simplicity. The feedback

signal in this circuit is connected to the non-inverting input terminal. So that the Op-amp

is working as a non inverting amplifier. Therefore, the feedback network need not provide

any phase shift. The circuit can be viewed as a Wien bridge with a series RC network in

one arm parallel network in adjoining arm. Resistors Ri and Rf are connected in the

remaining two arms. The condition of zero phase shift around the circuit is achieved by

balancing the bridge. The frequency of oscillation is the resonant frequency of the

balanced bridge and is given by the expression f0 =1

2𝜋RC . From the analysis of the circuit,

it can be seen that the feedback factor β=1/3 at the frequency of oscillation. Therefore, for

the sustained oscillation the amplifier must have a gain of 3. An FET circuit in association

with the wein bridge oscillator, helps the stabilization of the amplitude stabilization. The

N-channel JFET acts as a voltage controlled resistor. The dc voltage at the gate of FET

becomes more negative when amplitude of oscillation increases. Then gate of FET gets

reverse biased and effective resistance from drain to source increases. This causes to

decrease the gain according to the relation A = 1+𝑅0

𝑅𝑖 and amplitude is brought back to a

stable level. When the amplitude of oscillation decreases. Opposite effect occurs.

DESIGN:-

Wein Bridge Oscillator:-

The required frequency of oscillation f0 = 1 KHz

Given f0 = 1

2𝜋RC

Let C = 0.1µF. Then R = 1.6 k (Use 1.5 K std)


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Gain 1+𝑅𝑓

𝑅𝑖= 3

Let Ri = 1 K, Then Rf = 2.2 K ( Use 4.7 K Pot Std)

Wein Bridge Oscillator with Amplitude Stabilization:-

The required frequency of oscillation f0 = 1 KHz

Given f0 = 1

2𝜋RC

Let C = 0.1µF. Then R = 1.6 k (Use 1.5 K std)

Gain 1+𝑅𝑓

𝑅𝑖 = 3

Let Ri = 1 K

CIRCUIT DIAGRAM


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4. Square wave generator using 555 Timer

Square wave generator using 555 Timer is very simple, easy to design, very stable

and low cost. It can be used for timing from microseconds to hours. Due to these reasons

555 has a large number of applications and it is a popular IC among electronics hobbyists.

Above figure shows the circuit diagram of a 555 Timer wired in Astable Mode. 8th

pin and 1st pin of the IC are used to give power, Vcc and GND respectively. The 4th pin is

RESET pin which is active low and is connected to Vcc to avoid accidental resets. 5th pin

is the Control Voltage pin which is not used. So to avoid high frequency noises it is

connected to a capacitor C2 whose other end is connected to ground. Usually C2 = 0.01μF.

The Trigger (pin 2) and Threshold (pin 6) inputs are connected to the capacitor (C1) which

determines the output of the timer. Discharge pin (pin 7) is connected to the resistor Rb

such that the capacitor can discharge through Rb. Diode D connected in parallel to Rb is

only used when an output of duty cycle less than or equal to 50% is required.

Working

Since the Control Voltage (pin 5) is not used the comparator reference voltages

will be 2/3 Vcc and 1/3 Vcc respectively. So the output of the 555 will set (goes high)

when the capacitor voltage goes below 1/3 Vcc and output will reset (goes low) when the

capacitor voltage goes above 2/3 Vcc.

When the circuit is switched ON, the capacitor (C) voltage will be less than 1/3

Vcc. So the output of the lower comparator will be HIGH and of the higher comparator

will be LOW. This SETs the output of the SR Flip-flop. Thus the discharging transistor

will be OFF and the capacitor C starts charging from Vcc through resistor Ra &Rb. When

the capacitor voltage will become greater than 1/3 Vcc( less than 2/3 Vcc ), the output of

https://electrosome.com/555-timer-ic/

https://electrosome.com/555-timer-ic/


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both comparators will be LOW and the output of SR Flip-flop will be same as the previous

condition. Thus the capacitor continuous to charge.

When the capacitor voltage will becomes slightly greater than 2/3 Vcc the output

of the higher comparator will be HIGH and of lower comparator will be LOW. This resets

the SR Flip-flop. Thus the discharging transistor turns ON and the capacitor starts

discharging through resistor Rb. Soon the capacitor voltage will be less than 2/3 Vcc and

output of both comparators will be LOW. So the output of the SR Flip-flop will be the

previous state. So the discharging of capacitor continuous. When the capacitor voltage will

become less than 1/3 Vcc, the output SETs since the output of lower comparator is HIGH

and of higher comparator is LOW and the capacitor starts charging again. This process

continuous and a rectangular wave will be obtained at the output.

Design

Capacitor Charges through Ra and Rb.

Therefore,

TON = 0.693(Ra + Rb)C

Capacitor Discharges through Rb

TOFF = 0.693RbC

Duty Cycle = TON/(TON + TOFF)

Where TON and TOFF are the time period of HIGH and LOW of the output of 555.


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EXPERIMENT NO:8

FAMILIARIZATION OF ELECTRONIC SYSTEMS

1. Setting up of a PA System with different microphones, loud speakers and mixer

AIM

To setup a basic PA system.

THEORY

A Public Address or PA system is composed of 3 main components - a sound source, an

amplifier and a loudspeaker.

The sound source can be a number of things. It is normally a microphone or a playback

device such as a cassette deck or a CD player. The sound source produces an electrical

signal that represents the sound.

The amplifier is used to increase the level of the electrical signal from the sound source

so that it can be heard at sufficient volume from the loudspeaker.

Finally, the loudspeaker is the device which converts the electrical impulses from the

amplifier into vibrations in the air which our ear interprets as sounds.

Additionally, you will normally be dealing with multiple sound sources. In order to

control these properly a Mixer is used to add the sounds together so that a single signal

can be sent to the Amplifier. Mixers also have other roles. Some sound sources have very

weak signals (microphones especially) which are not suitable for direct connection to an

amplifier. The mixer provides what is known as a Pre-amplifier that will boost the input

signal up to a suitable level. This is also referred to as Input Gain

Sound sources

Sound sources vary widely. They can be microphones for capturing sounds from voices

or instruments. They can be from a recorded media such as CD or Minidisc or Cassette.

Or, in broadcast situations, they may be from a radio transmission or the telephone.

Whatever the source is we need to understand its properties so that we can connect it

properly to our PA system.

Microphones produce a very weak signal. They are essentially the reverse of a

loudspeaker where the vibrations in the air cause movements in a small diaphram in the

microphone capsule. The resulting electrical signal is very weak and needs to be boosted

before it can be sent to an amplifier. This is the job of a Pre-amplifier. These devices can

be found in most mixers as mentioned above but they can also exist as separate units in

some cases.

Amplifiers

As we said earlier, amplifiers take a line-level signal and boost it to the levels required to

drive a loudspeaker. We refer to all these amplifiers as Power Amplifiers as they handle

the high powers required to drive loudspeakers.


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Power

The main parameter you will pay attention to when selecting an amplifier is the Output

Power. This is expressed in Watts - e.g. 650 Watts. Care must be taken here as the power

delivered by an amplifier depends on the load being driven by the amplifier - in our case,

the loudspeaker.

Load

The load in this case is the loudspeaker. Each loudspeaker has an electrical characteristic

called the Impedance and is expressed in Ohms (W). It is a measure of the resistance

offered by the loudspeaker.

Loudspeakers

The loudspeaker is the final link in the chain. In essence it is a very simple device but is

takes careful design and construction to produce a unit that delivers clear, precise sound.

A loudspeaker is essentially a box or cabinet containing one or more Drivers that produce

the actual sound.

Impedance

We mentioned Impedance when we talked about amplifiers. This is a measure of the

Load that the speaker represents to the amplifier. It is measured in Ohms (W). Most

speakers have an Impedance of either 4W, 8W or 16W. This figure must be taken into

account when choosing the correct amplifier to use.

But what happens when you want to connect two or more loudspeakers to the same

amplifier channel? Does the impedance change? Well, yes it does, but not as you may

expect. When speakers are connected together they are connected in parallel. When this

happens the following maths applies:

1

𝑇𝑜𝑡𝑎𝑙 𝐼𝑚𝑝 =

1

𝐼𝑚𝑝 𝐴+

1

𝐼𝑚𝑝 𝐵+ ……

To deal with more than two loads you just keep on adding terms to the right. So two 8W

speakers would give a total of 4W and three 8W loads would give you a total load of

2.67W. Be careful not to make the load too small. Most amplifiers have a minimum load

that they can drive, 2W being the common minimum. Always check the specifications of

the equipment.

Mixer

If we want to combine the audio signals from more than one source the obvious thought

would be to connect all the wires together. In practice this doesn't really work due to

various electrical properties such as impedance, phase cancelation and noise. What we

require is a device that combines the signals properly and gives us control over the

balance between each input. This is the job of the Mixer.

In its simplest form a mixer has several inputs and a single output where the combined

signal comes out. To give us a little more control, individual level (volume) controls are

fitted to the inputs and a master level control to the output. This then allows us to not only


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control the overall output level from the unit but also the balance between the individual

inputs. Most mixers have more functionality than this and we need these extra functions

when setting up a PA system.

We will now describe the functions of a typical Mixing Desk (also referred to by some as

a Console). The desk can be split into 3 main areas.

The Channel Strip - This contains the controls for each input. Multiple channel strips are

to be found on a mixer, normally in multiples of 4 or 8 - e.g. 4,8,12,16,24,32. This simply

corresponds to the number of inputs that the desk can support.

The Master Section - This containes the Output level controls and other controls that

affect the overall output of the mixer.

The Connection Panel - This contains the various connectors for attaching the inputs and

outputs and other auxiliary equipment.

We will now take a look at each of these in detail. It should be noted that no two mixers

are the same and the one you are using may have more or less features than are described

here. All the basics operating procedures, however, are the same.

Equaliser

The EQ or Equaliser section allows control over the tone of the audio signal. Simple

mixers may just have two controls - Bass and Treble. Slightly better ones have a Mid-

band control too. The best ones have Parametric control that allow you to select the

frequency on which the control is acting. The one shown in the diagram has 2 parametric

bands allowing for good control over the signal. EQ is used not only to control how

something 'sounds' but can also be used to help correct problems such as feedback and to

create particular effects. If you use more than one brand of mixers you may hear

differences between the EQ sections from different manufacturers. This is one of the

reasons that some engineers favour a particular brand of mixing desk.

Cables & Connections

Cables, although among the cheapest items in a PA, are very important. These carry the

audio signals between components and should therefore be chosen carefully in order to

minimise losses and interference which could degrade the resulting sound.


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2. Assembling of desktop computer

AIM

To assemble a desktop computer.

THEORY

Computer Parts

A computer is made up of a case, also called a chassis, which houses several internal

components, and the external components, including peripherals. Inside the case go the

following internal parts:

• Power Supply/PSU power supply unit: It converts the outlet power, which is alternating

current (AC), to direct current (DC), which is what the internal components require, as

well as providing appropriate voltages and currents for the various internal components.


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• Motherboard/mainboard: As the name indicates, this is the electronic centerpiece of the

computer, everything else connects to the motherboard.

• Processor/CPU central processing unit: It is the ―brain‖ of the computer, most actual

computation takes place here.

• RAM random access memory: It is the ―short-term memory‖ of a computer, used by the

CPU to store program instructions and data upon which it is currently operating. Data in

RAM is lost when the computer is powered off, thus necessitating a hard drive.

• Hard Drive/Hard Disk: It is the ―long-term memory‖ of the computer, used for persistent

storage i.e. the things stored on it remain even when the computer is powered down. The

operating system, and all your programs and data are stored here.

• Optical Drive device for reading/writing optical disks: May read CDs, DVDs, or other

optical media, depending on the type. It is essential for installing many operating systems

and programs. It may be able to write some of these discs, as well. Some people like to

have two such drives for copying disks.

• Video Card/Graphics Card/GPU: It does processing relating to video output. Some

motherboards have an ―onboard‖ GPU built in so you don‘t need (but may add) a separate

video card. Otherwise, you will need a video card. These plug into a slot on the

motherboard and provide a place to connect a monitor to your computer.

On top of the internal components listed above, you will also need these external

components:

• Keyboard for typing on. Many motherboards won‘t even boot without a keyboard

attached.

• Mouse for pointing and clicking. Unless you chose a text-based operating system, you

will likely want one of these.

• Monitor this is where the pretty pictures go. They come in many forms, the most

common being CRT and LCD.


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COMPUTER ASSEMBLY - PROCEDURE

Motherboard

Find the motherboard standoffs that should have come with the case. They are

screws, usually brass, with large hexagonal heads that are tapped so you can fasten screws

into the top. Remove the I/O Shield from the back of the case where the ports on the back

of the motherboard will fit, and put in the I/O Shield that came with your motherboard.

There may be small metal tabs on the inside of this face plate, if so you may have to adjust

them to accommodate the ports on the back of the motherboard.

Some case styles make it difficult to install the motherboard or the CPU with the power

supply installed. If the power supply is in your way, take it out and set it aside (we‘ll put it

back in later).

Now locate the screw holes on your motherboard and find the corresponding holes

on the motherboard plate (or tray) in the case. Put a standoff in each of these holes on the

tray and position the motherboard so that you can see the holes in the top of the standoffs

through the screw holes in the motherboard. Now is the time to make sure the ports on the

motherboard are mating with the back plate you just installed, and make any necessary

adjustments. The small metal tabs are intended to make contact with the metal parts of the

connections on the back of the motherboard and ground them, but you may have to bend

these tabs a bit to get the ports all properly mounted.

Now fasten a screw through each of the motherboard screw holes into the standoffs

underneath. These screws should be snug but not tight, there is no reason to torque down

on them, hand tight is fine, otherwise you can damage the motherboard.

CPU

Installing the CPU, and the CPUs heatsink and fan, are by far the most difficult steps youll

have to complete during your build. Some operations, especially installing the heatsink/fan

combination, can require pretty firm pressure, so don‘t be afraid to push a little harder if

you are sure everything is set up correctly.

The details of the installation process differ in slight but important ways for each

manufacturers processors, and even within a manufacturers product line. Therefore, for

these details, you should rely on the instructions that are provided with the CPU.


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The two things that go wrong the most often and most expensively (minimum of a killed

CPU, sometimes more) in building one‘s own computer are both related to the CPU and

its cooler:

1. Switching the computer on ―just to see if it works‖ before adding any CPU cooling unit.

Without cooling, CPUs heat up at extreme rates (a CPU heats up anywhere between ten

times and a thousand times as fast as a cooking area on your stove!) By the time you see

the first display on the screen, your CPU will already be severely overheating and might

be damaged beyond repair.

2. Mounting the CPU cooler improperly. Read the instructions that came with your CPU

and cooler very carefully and ensure you are using all components in the correct order and

correct place.Tighten the cooler using only the specified holding devices—if you did

everything right, they will fit. If they don‘t fit, check your setup—most likely something is

wrong. After mounting the cooler, connect any power cables for the fan that is attached

onto the cooler.

RAM

Next, you will need to install your RAM (random access memory). To install the

RAM modules, first push on the levers (white plastic in the picture) on either side of the

DIMM socket, so that they move to the sides. Do not force them, they should move fairly

easily. Put the RAM module in the socket. Line up the notch in the center of the module

with the small bump in the center of the RAM socket, making sure to insert it the right

way. Push down on the module until both levers move up into the notches on the sides of

the module. There should be a small ―snap‖ when the module is fully seated. Although this

does require a fair bit of force, don‘t over do it or you may break the RAM module.

Take a good look at your seated RAM, if one side seems to be higher than the

other, odds are it‘s improperly seated—take it out and try again. As you handle the RAM,

try not to touch the copper stripes you can see along the bottom edge, as doing so is the

best way to damage the part. Start adding RAM at the slot labeled ―Bank 0‖ or ―DIMM 1‖.

If you don‘t have a stick in ―Bank 0‖ or ―DIMM 1‖ the system will think there is no RAM

and won‘t boot.

On newer motherboards with 4 slots, you‘ll see alternating colours. For example,

slot 1 is blue, slot 2 is black, slot 3 is blue, slot 4 is black. If you were to put 1 gigabyte of

RAM in your PC, it‘s best to use dual channel 512MBx2 sticks. Put the first 512MB stick


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in slot 1, and put the 2nd

stick in slot 3 (the two slots that are blue)—leaving slot 2 empty.

This will give you better performance, vs. putting 1GB in slot 1, or two 512MB sticks in

slot 1 and 2.

Power Supply

Installing your power supply is pretty straightforward, if it came with your case it

was preinstalled and if you took it out earlier to get the motherboard in, now is the time to

put it back. Otherwise a few moments of screwdriver work will get the job done.

Generally there will be a bracket on the top of the case where the power supply is mounted

and a few screws used to fix it in place. Some cases place the PS differently, see the

documentation that came with yours.

If your power supply has a switch to select 115v or 220v make sure it is set properly, this

is important. Many newer power supplies can automatically select and dont have such a

switch. Once you get the power supply installed you should plug the main power, a 20 or

24 pin plug, into the motherboard. There may also be an additional four or eight pin power

lead on the motherboard that needs to be plugged in, this is usually located near the

processor socket. Make sure you check the motherboard documentation carefully for the

location of the power sockets.

Installing drives

Next install the hard drive and optical drives. How a drive is physically installed

will depend on the case. When using an IDE cable, plug the two connectors that are closer

together into the 2 drives, and the third to the controller or motherboard. The connector

furthest from the board should be attached to the drive set as Master. Make sure the drive

that you will install your OS on is the primary master. This is the master drive on the

Primary IDE bus which is usually the IDE 40 pin port on the motherboard labelled

Primary or IDE 1.

Other connections

In order to turn the computer on, you will need to connect the power button and while

you‘re at it, you might as well do the reset buttons and front panel lights as well. There

will be a set of pins, usually near the front of the motherboard to which you will attach the

cables that should have been supplied with the motherboard.


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These will plug into the front of the case. The plugs in the front of the case will be

labelled. The pins on the motherboard may be labelled as well. The documentation that

came with your case and motherboard should tell where these connectors are. The front

panel LEDs are polarized: usually the positive wire is white. In addition, you can connect

any case-specific ports if they are supported by the motherboard.

Power up

Before power turns ON, you want to have the computer open, so that you can see

all of the fans, and youll need to connect a monitor and a keyboard and a mouse. Monitors

will either have a VGA or a newer DVI plug. Most monitors use VGA connectors, and so

most graphics cards have VGA output. There are two standard connectors for mice and

keyboards; PS/2 connectors and the more modern USB connectors. Plug the mouse and

keyboard in the appropriate slot.

Turn on the monitor, then press the power button, and observe the inside of the

open machine. (Do not touch any part of the inside of the machine while it is powered up).

The first thing to look for is that the CPU cooler fan spins up, if it does not, cut the power

immediately. This fan should start up right away; something is wrong if it doesn‘t and

your CPU is in danger of overheating so stop now and troubleshoot.

If the CPU fan spins up, check that all the other fans that should be spinning case

fans and fans on the power supply and video card (if installed) are also spinning. Some of

these fans may not spin up until a temperature threshold is passed, check your

documentation if anything is not spinning. If the fans spin, you can turn your attention to

the monitor, what you are hoping to see is the motherboards splash screen, usually

featuring the manufacturer‘s logo. If you see this, take a moment to bask in the glow, you

have built a computer!

Note: If it does not occur, if smoke appears, or if the computer doesn‘t do anything,

unplug the power cord immediately and check the steps above to make sure you haven‘t

missed anything. Give special attention to the cables and power connections. If the

computer does appear to come on, but, you hear beeps, listen carefully to the beeps, turn

the computer off, and refer to your motherboard‘s manual for the meaning of the beeps.

Some boards have an optional diagnostic device, usually a collection of LEDs, which

when properly plugged in will inform you of the nature of the problem. Instructions for


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installing this as well as the meaning of its display should be in the manual for the

motherboard. If the computer turns on but the only thing that comes on is your power

supply, turn it off. This probably means something is shorted, and leaving it on could

damage the parts.

Installing softwares

Now that you have got a functioning computer, you will need to install some software if

you are going to do anything with it. An operating system must come first, then hardware

drivers (so that the operating system can address your hardware) followed by security

software and utilities. Choosing between Microsoft Windows, GNU/Linux, or one of the

other operating systems is largely dependent on what software you need to run. Microsoft

Windows is better in terms of software availability, hardware compatibility and support,

but GNU/Linux wins in terms of stability, ability to run on older equipment, and cost.

For installing operating system, push the button on the front of the PC, put the CD-ROM

in your optical drive, and follow the on-screen instructions.

Steps for Assembly:

1. Prepare the Mainboard (motherboard). If you want to assemble the well-liked

device, you should use Intel i3,i5,i7 Mainboard.

2. Mount the CPU in the socket of the Mainboard. You must choose the correct CPU

for your motherboard, and install it according to it's instructions. Be careful not to

install the CPU in wrong. Not only would your computer not work, it could

short-circuit and damage your motherboard.


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3. Connect the CPU cooler to the Mainboard.

4. Attach the RAM(memory) modules in the corresponding slots. The motherboard

should have rows of slots that have 2 or 3 sections that are different lengths. Make

sure the pins on the RAM cards line up with the pins on the motherboard

connector. Don't get the RAM slots mixed up with PCI slots. The PCI slots are

usually wider.

5. Open the case and mount the power supply which is M-ATX type. Make sure to

connect all the connections to the drives and the motherboard.


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6. Attach the Mainboard back plate to the case and check the Mainboard mounting

positions. The motherboard's instructions should tell the position of the motherboard.

7. Suitably position the Mainboard in the case.

8. Mount the Hard disk and connect it to the power supply and the

motherboard. There should be separate connections for the power supply and the

motherboard. In SATA Hard disk case, should remove the jumper.


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9. Connect the 20 or 24 pin ATX connector and the 4-pin power supply control

connector to the motherboard.

10. Mount the DVD-ROM drive. After connecting the ATA cable to the device, hook it

up to the power supply.

11. Finally, select a compatible operating system, and follow the instructions to

install.


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3. Familiarization of components used in robotics

AIM

To familiarize with various Components used in robotics such as;

Sensors

Motors

Batteries

THEORY

A robot is ―intelligent‖, a man made device that can move by itself, whose motion

can be modeled, planned, sensed and controlled and who‘s motion and behavior can be

influenced by programming. A robot is a general purpose, programmable manipulator. In

practice it is usually an electromechanical system which by its movements and

appearance conveys that it has intent of its own.

a). Sensors Used in Robotics

The use of sensors in robots has taken them into the next level of creativity. Most

importantly, the sensors have increased the performance of robots to a large extent. It also

allows the robots to perform several functions like a human being. The robots are even

made intelligent with the help of Visual Sensors (generally called as machine vision or

computer vision), which helps them to respond according to the situation.

Different types of sensors

There are plenty of sensors used in the robots, and some of the important types are listed

below.

Light sensors

A Light sensor is used to detect light and create a voltage difference. The two main light

sensors generally used in robots are Photo resistor and Photovoltaic cells. Other kinds of

light sensors like Phototubes, Phototransistors, CCD‘s etc. are rarely used.

Photo resistor is a type of resistor whose resistance varies with change in light intensity;

more light leads to less resistance and less light leads to more resistance. These

inexpensive sensors can be easily implemented in most light dependant robots.


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Fig: Light Sensors

Sound Sensor

As the name suggests, this sensor (generally a microphone) detects sound and returns a

voltage proportional to the sound level. A simple robot can be designed to navigate based

on the sound it receives. Imagine a robot which turns right for one clap and turns left for

two claps. Complex robots can use the same microphone for speech and voice recognition.

Fig: Sound Sensor (Mic)

Implementing sound sensors is not as easy as light sensors because Sound sensors generate

a very small voltage difference which should be amplified to generate measurable voltage

change.

Temperature Sensor

Tiny temperature sensor ICs provide voltage difference for a change in temperature. Few

generally used temperature sensor IC‘s are LM34, LM35, TMP35, TMP36, and TMP37.


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Fig: Temperature Sensor LM35

Contact sensors

Contact sensors are those which require physical contact against other objects to trigger. A

push button switch, limit switch or tactile bumper switch are all examples of contact

sensors. These sensors are mostly used for obstacle avoidance robots. When these

switches hit an obstacle, it triggers the robot to do a task, which can be reversing, turning,

switching on a LED, Stopping etc. There are also capacitive contact sensors which react

only to human touch.

Fig: Contact sensor (Push Button Switch

Proximity Sensors

This is a type of sensor which can detect the presence of a nearby object within a given

distance, without any physical contact. The working principle of a Proximity sensor is

simple. A transmitter transmits an electromagnetic radiation or creates an electrostatic

field and a receiver receives and analyzes the return signal for interruptions. There are


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different types of Proximity sensors and we will discuss only a few of them which are

generally used in robots.

Infrared (IR) Transceivers: An IR LED transmits a beam of IR light and if it finds

an obstacle, the light is simply reflected back which is captured by an IR receiver.

Few IR transceivers can also be used for distance measurement.

Ultrasonic Sensor: These sensors generate high frequency sound waves; the

received echo suggests an object interruption. Ultrasonic Sensors can also be used

for distance measurement.

Photo resistor: Photo resistor is a light sensor; but, it can still be used as a

proximity sensor. When an object comes in close proximity to the sensor, the

amount of light changes which in turn changes the resistance of the Photo resistor.

This change can be detected and processed.

Fig: IR Transceivers

Positioning sensors

Positioning sensors are used to approximate the position of a robot, some for indoor

positioning and few others for outdoor positioning.

GPS (Global Positioning System): The most commonly used positioning sensor is

a GPS. Satellites orbiting our earth transmit signals and a receiver on a robot

acquires these signals and processes it. The processed information can be used to

determine the approximate position and velocity of a robot. These GPS systems are

extremely helpful for outdoor robots, but fail indoors. They are also bit expensive

at the moment and if their prices fall, very soon you would see most robots with a

GPS module attached.


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b). Motors Used in Robotics

Electric motors are used to ―actuate‖ something in your robot: its wheels, legs, tracks,

arms, fingers, sensor turrets, or weapon systems.

DC Motor

In a continuous DC motor, application of power causes the shaft to rotate

continually. The shaft stops only when the power is removed, of if the motor is stalled

because it can no longer drive the load attached to it. Typical DC motors may operate on

as few as 1.5 Volts or up to 100 Volts or more. Roboticists often use motors that operate

on 6, 12, or 24 volts because most robots are battery powered, and batteries are typically

available with these values.

Fig: DC Motor

Stepper Motor

Stepper motors are DC motors that move in discrete steps. They have multiple coils that

are organized in groups called "phases". By energizing each phase in sequence, the motor

will rotate, one step at a time. Stepper motors have several electromagnetic coils that must

be powered sequentially to make the motor turn, or step, from one position, to the next. By

reversing the order that the coils are powered, a stepper motor can be made to reverse

direction. The rate at which the coils are respectively energized determines the velocity of

the motor up to a physical limit. Typical stepper motors have two or four coils.


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Fig: Stepper Motor

Servo Motor

Standard servo motors have three wires, which are for power ( 4 – 6 V), ground

and control. The size and shape of the servo motors are dependent on the application. RC

servo motor are the common type of servo motors used in robotics and hobby applications

due to their affordability, reliability, and simplicity of control by microprocessors.RC

servo motors are low power servos that can be powered from small batteries and other DC

supplies in the range of 100 mA to 2 A. There are also high power servo motor types

which are powered from AC supplies and used in industrial applications.

Although the microcontroller (the robot‘s brain) decides the speed and direction of

the motors, it cannot drive them directly because of its very limited power (current and

voltage) output. The motor controller, on the other hand, can provide the current at the

required voltage but cannot decide how fast the motor should turn.

Thus, the microcontroller and the motor controller have to work together in order to make

the motors move appropriately.


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Fig: Servo Motor

Small motors are engineered for applications where compactness is valued over

torque. While there are small high-torque motors, these tend to be expensive because they

use rare earth magnets, high efficiency bearings, and other features that add to their cost.

Large motors may produce more torque, but also require higher currents. High

current motors require larger capacity batteries, and bigger control circuits that won‘t

overheat and burn out under the load. Therefore, match the size of the motor with the rest

of the robot. Don‘t overload a small robot with a large motor when big size isn‘t

important.

When decided on the size of the motor, compare available torque after any gear

reduction. Gear reduction always increases torque. The increase in torque is proportional

to the amount of gear reduction: if the reduction is 3:1, the torque is increased by about

three times.

c). Batteries Used in Robotics

Batteries are the main component of a robotic system. Batteries can be classified into

rechargeable or non-rechargeable. Non-rechargeable batteries deliver more power based

on their size, and are suitable for certain applications.

Alkaline batteries are inexpensive, and lithium batteries, on the other hand exhibit a longer

shelf life and better performance.Common rechargeable batteries such as nickel-cadmium

(NiCd) and lead acid batteries deliver a smaller voltage than alkaline batteries. They are

found in battery packs along with specialized power connectors. Gelled lead acid batteries


MCET Pathanamthitta

are widely used and capable of providing power of up to 40Wh/kg.Lithium-ion, nickel

metal hydride and silver zinc batteries are some of the other rechargeable battery

technologies that offer significantly increased energy density.

Photovoltaic Cells

Photovoltaic or solar cells can be used to charge the batteries of the robotic systems. They

are used in conjunction with a capacitor and can be charged up to a set voltage level and

then be discharged via the movements of motor. These cells are chiefly used in BEAM

robots.


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APPENDIX – A

STANDARD VALUES OF COMPONENTS

Typical Standard value Resistors

10% TOELRANCE RESISTORS

Ω Ω Ω KΩ KΩ KΩ MΩ MΩ

− 10 100 1 10 100 1 10

− 12 120 1.2 12 120 1.2 12

− 15 150 1.5 15 150 1.5 15

− 18 180 1.8 18 180 1.8 18

− 22 220 2.2 22 220 2.2 22

2.7 27 270 2.7 27 270 2.7 −

3.3 33 330 3.3 33 330 3.3 −

3.9 39 390 3.9 39 390 3.9 −

4.7 47 470 4.7 47 470 4.7 −

5.6 56 560 5.6 56 560 5.6 −

6.8 68 680 6.8 68 680 6.8 −

8.2 82 820 8.2 82 820 8.2 −


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5% TOLERANCE RESISTORS

Ω Ω Ω KΩ KΩ KΩ MΩ MΩ

− 10 100 1 10 100 1 10

− 11 110 1.1 11 110 1.1 11

− 12 120 1.2 12 120 1.2 12

− 13 130 1.3 13 130 1.3 13

− 15 150 1.5 15 150 1.5 15

− 16 160 1.6 16 160 1.6 16

− 18 180 1.8 18 180 1.8 18

− 20 200 2 20 200 2 20

− 22 220 2.2 22 220 2.2 22

− 24 240 2.4 24 240 2.4 −

2.7 27 270 2.7 27 270 2.7 −

3 30 300 3 30 300 3 −

3.3 33 330 3.3 33 330 3.3 −

3.6 36 360 3.6 36 360 3.6 −

3.9 39 390 3.9 39 390 3.9 −

4.3 43 430 4.3 43 430 4.3 −

4.7 47 470 4.7 47 470 4.7 −

5.1 51 510 5.1 51 510 5.1 −

5.6 56 560 5.6 56 560 5.6 −

6.2 62 620 6.2 62 620 6.2 −

6.8 68 680 6.8 68 680 6.8 −

7.5 75 750 7.5 75 750 7.5 −

8.2 82 82 8.2 82 82 8.2 −

9.1 91 910 9.1 91 910 9.1 −


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Typical Standard value Capacitors

STANDARD VALUE CAPACITORS

Code (pF) (nF) (μF) Code (pF) (nF) (μF)

100 10 0.01 0.00001 472 4700 4.7 0.0047

150 15 0.01

5 0.000015 502 5000 5.0 0.005

220 22 0.02

2 0.000022 562 5600 5.6 0.0056

330 33 0.03

3 0.000033 682 6800 6.8 0.0068

470 47 0.04

7 0.000047 103 10000 10 0.01

101 100 0.1 0.0001 153 15000 15 0.015

121 120 0.12 0.00012 223 22000 22 0.022

131 130 0.13 0.00013 333 33000 33 0.033

151 150 0.15 0.00015 473 47000 47 0.047

181 180 0.18 0.00018 683 68000 68 0.068

221 220 0.22 0.00022 104 10000

0 100 0.1

331 330 0.33 0.00033 154 15000

0 150 0.15

471 470 0.47 0.00047 254 20000

0 200 0.2

561 560 0.56 0.00056 224 22000

0 220 0.22

681 680 0.68 0.00068 334 33000

0 330 0.33

751 750 0.75 0.00075 474 47000

0 470 0.47

821 820 0.82 0.00082 684 68000

0 680 0.68

102 1000 1.0 0.001 105 10000

00 1000 1.0

152 1500 1.5 0.0015 155 15000

00 1500 1.5

202 2000 2.0 0.002 205 20000

00 2000 2.0

222 2200 2.2 0.0022 225 22000

00 2200 2.2

332 3300 3.3 0.0033 335 33000

00 3300 3.3

new ec 110 electronics engineering workshop · 2015. 10. 8. · electronics engineering workshop...

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