ENGR. RIZZA T. LOQUIASENGR. RIZZA T. LOQUIASECE Department Chairperson - CSPCECE Department Chairperson - CSPC

ElectronicsElectronics

  branch of engineering and applied branch of engineering and applied physics dealing with the design and physics dealing with the design and application of devices, usually application of devices, usually electronic circuits, the operation of electronic circuits, the operation of which depends on the flow of which depends on the flow of electrons for the generation, electrons for the generation, transmission, reception, and storage transmission, reception, and storage of information. of information.

TREE OF KNOWLEDGE FOR ELECTRONICS EDUCATION

APPLICATIONS OF APPLICATIONS OF ELECTRONICS ELECTRONICS

History shows that electronics History shows that electronics started in the pioneer days of radio started in the pioneer days of radio communicationscommunications

In addition to its use in radio and television, electronics is used in almost all industries for control functions, automation, and computing.

Groups of Electronics ApplicationsGroups of Electronics Applications

Communications electronicsCommunications electronics Power electronicsPower electronics Digital electronicsDigital electronics Automotive electronicsAutomotive electronics Industrial electronicsIndustrial electronics Medical electronicsMedical electronics

Electronic DevicesElectronic Devices

Electronics has many applications but there are only a few basic types of components that are used for all the different kinds of equipment. Each type has variations for specific uses.

Generally, electronic components are classified as

1. Active components

2. Passive components

Electronic ComponentsElectronic Components SemiconductorsSemiconductorsExamples: diodes, transistors, Integrated CircuitsExamples: diodes, transistors, Integrated Circuits

Electron tubesElectron tubesExamples: vacuum-tubes, cathode-ray tubesExamples: vacuum-tubes, cathode-ray tubes

Visual Display DevicesVisual Display DevicesExamples: light-emitting diodes (LED) and liquid-crystal display (LCD)Examples: light-emitting diodes (LED) and liquid-crystal display (LCD)

ResistorsResistors

Capacitors or condensersCapacitors or condensers

Inductors or coilsInductors or coils

ResistorResistor- Limits the amount of current or Limits the amount of current or

divide the voltage in a circuitdivide the voltage in a circuit- Unit of resistance is the ohm (Unit of resistance is the ohm ())

Type SymbolSymbol Function

Fixed resistor Limits current and completes circuit

Variable resistor Varies current or voltage; used for volume, contrast, and tone controls; needed for many electrical adjustments

CapacitorCapacitor

- Made up of two conductor plates Made up of two conductor plates separated by an insulator (dielectric)separated by an insulator (dielectric)

- Basic function is to concentrate the Basic function is to concentrate the electric field of voltage applied electric field of voltage applied across the dielectric, thus across the dielectric, thus accumulating and can store electric accumulating and can store electric charge from the voltage source.charge from the voltage source.

Unit of capacitance is the farad (F)Unit of capacitance is the farad (F)

TYPE SYMBOLSYMBOL FUNCTION

Fixed capacitor Stores charge in dielectric; passes ac voltage but blocks dc voltage

Electrolytic capacitor

Fixed value with large C but has polarity

Variable resistor Variable capacitor; used for tuning

Inductors Inductors - An inductor is a coil of wire also An inductor is a coil of wire also

called called chokechoke..- Unit of inductance is the henry (H)Unit of inductance is the henry (H)

TYPE SYMBOL FUNCTION

Air-core inductor Concentrates magnetic field; for radio frequencies

Iron core For 60-Hz and audio frequencies

Variable powered-iron core

Variable inductance; used for tuning

Iron-core transformer Increases or decreases ac voltage fro primary to secondary winding

Electronic CircuitsElectronic Circuits

Components in a Transistor Radio

Example of a hi-tech Example of a hi-tech electronic gadgetelectronic gadget

Schematic Diagram

Electronic components mounted on top of a printed circuit board

Electronic equipment/gadget for human use

Basic Concepts of Basic Concepts of Semiconductor DevicesSemiconductor Devices

Classification of MaterialsClassification of Materials ConductorsConductors

is a substance, body or material …is a substance, body or material …

……which has more electrons that are free to movewhich has more electrons that are free to move

……which supports charge carrier flowwhich supports charge carrier flow

……which allows electric current to flow with easewhich allows electric current to flow with ease

……which has a very low electrical resistancewhich has a very low electrical resistance

……with less than four valence electronswith less than four valence electrons

Examples: metals, electrolytes, and ionized gasExamples: metals, electrolytes, and ionized gas

InsulatorInsulator

is a material with more than four is a material with more than four valence electrons; has valence electrons; has characteristics that are opposite to characteristics that are opposite to that of a conductor.that of a conductor.

Example: glass, mica, rubberExample: glass, mica, rubber

SemiconductorsSemiconductors

Is a material with exactly four valence Is a material with exactly four valence electrons; has characteristics in between electrons; has characteristics in between conductors and insulators.conductors and insulators.Examples: Elementary semiconductors (Group IV A)Examples: Elementary semiconductors (Group IV A)

Silicon (Si)Silicon (Si)

Germanium (Ge)Germanium (Ge)

Compound semiconductors (IIIA-VA)Compound semiconductors (IIIA-VA)

Gallium Arsenide (GaAs)Gallium Arsenide (GaAs)

Aluminum Arsenide (AlAs)Aluminum Arsenide (AlAs)

Gallium Phosphide (GaPGallium Phosphide (GaP))

The wider the energy-gap, the harder the material can produce free electrons.

Conductors produce free electrons easily than semiconductors.

Germanium produces more free electrons than silicon and relatively has higher leakage current.

Germanium devices like diode, has lower switch-on voltage than silicon diode due to its lower energy-gap.

Properties of SemiconductorsProperties of Semiconductors

Negative temperature coefficient (i.e. resistance Negative temperature coefficient (i.e. resistance decreases with higher temperaturedecreases with higher temperature

Their conductivities lie between that of conductor Their conductivities lie between that of conductor and insulator at room temperatureand insulator at room temperature

The conductivity can be improved by the addition The conductivity can be improved by the addition of impuritiesof impurities

The current in the semiconductor is constituted The current in the semiconductor is constituted by the movement of holes and electronsby the movement of holes and electrons

Covalent Bonding of SemiconductorsCovalent Bonding of Semiconductors

In semiconductor materials, the atoms are held together or bonded by sharing their valence electrons (covalent bond).

With covalent bonds for the semiconductor elements Si and Ge, it becomes possible to add impurity elements that results in the desired electrical characteristics.

The process of adding impurity element is called DOPING.

Classification of SemiconductorsClassification of Semiconductors

N-TYPE

SEMICONDUCTOR

INTRINSIC (pure) EXTRINSIC (DOPED)

P-TYPE

Extrinsic semiconductorsExtrinsic semiconductors When intrinsic material is doped, it will When intrinsic material is doped, it will

become extrinsicbecome extrinsic n-type semiconductor material is formed n-type semiconductor material is formed

by adding by adding donordonor impurities, such as impurities, such as pentavalentpentavalent (with five valence electrons) (with five valence electrons)

Common pentavalent elements: P, Sb, AsCommon pentavalent elements: P, Sb, As

p-type semiconductor is formed by adding p-type semiconductor is formed by adding acceptoracceptor impurities, such as impurities, such as trivalent trivalent (with (with three valence electronsthree valence electrons

Common trivalent elements: B, In, GaCommon trivalent elements: B, In, Ga

Ideally, n-type materials have negative carriers only, but practically there are a few numbers of positive carriers

For n-type materials, the majority carriers are electrons, minority carriers are the holes.

When a potential difference is applied across the n-type materials:

•Holes flow from positive to negative

•Electrons flow from negative to positive

•The net flow will be that of electrons

Ideally, p-type materials have positive carriers only, but practically there are a few numbers of negative carriers

For p-type materials, the majority carriers are holes, minority carriers are the electrons.

When a potential difference is applied across the n-type materials:

•Holes flow from positive to negative

•Electrons flow from negative to positive

•The net flow will be that of holes

When a p-type and n-type materials are brought When a p-type and n-type materials are brought together, they form a so-called together, they form a so-called pn-junctionpn-junction

At the junction, the electrons from the n-type and holes from the p-type attract each other and combine, canceling their net charge.

Due to the combination and cancellation of electrons and holes at the junction, the junction will have no more charged carriers, thus it is called depletion region

The pn-Junction OperationThe pn-Junction OperationWhen a voltage is applied at p-type and n-type materials, the junction will either narrow or widens depending on the polarity of the applied voltage.

Forward-biased operation – the narrowed junction enables current to flow

Reverse-biased operation- the widened junction blocks the current flow.

The Junction DiodeThe Junction Diode

The required voltage across the junction of the diode before forward current can flow is called the threshold voltage.

For silicon diode, Vth = 0.7 V

For germanium diode, Vth = 0.3 V

The most basic semiconductor diode is constructed and operated based on the pn-junction

Main uses of diodesMain uses of diodes

Power supply rectifierPower supply rectifier

Signal detectorSignal detector

Digital logic gatesDigital logic gates

There are many different types of diodes for special applications

Transistor Transistor

Consists of three electrode:Consists of three electrode:emitter – supplies free chargesemitter – supplies free chargesbase – controls the flow of chargesbase – controls the flow of chargescollector – collects the charges from the emittercollector – collects the charges from the emitter

Name derived from “transfer resistor” meaning Name derived from “transfer resistor” meaning that it can transfer its internal resistance from low that it can transfer its internal resistance from low in the emitter-base circuit to a much higher R in in the emitter-base circuit to a much higher R in the collector-base circuit.the collector-base circuit.

- A semiconductor device that can generate, amplify or control electrical signal.

Bipolar Junction TransistorsThe bipolar junction transistor consists of three layers of highly purified silicon (or germanium) to which small amounts of boron (p-type) or phosphorus (n-type) have been added. The boundary between each layer forms a junction, which only allows current to flow from p to n. Connections to each layer are made by evaporating aluminum on the surface; the silicon dioxide coating protects the nonmetalized areas. A small current through the base-emitter junction causes a current 10 to 1000 times larger to flow between the collector and emitter. The many uses of the junction transistor, from sensitive electronic detectors to powerful hi-fi amplifiers, all depend on this current amplification.

Bipolar Junction Transistors

Transistor actionTransistor action

The collector current is controlled by the The collector current is controlled by the emitter-base circuit and requires:emitter-base circuit and requires:- the emitter has heavy doping to supply - the emitter has heavy doping to supply free chargesfree charges- the base has only light doping and is very - the base has only light doping and is very thin.thin.- the collector voltage is relatively high.- the collector voltage is relatively high.

requires proper requires proper biasingbiasing to obtain desired to obtain desired operationoperation

Semiconductor materials such as silicon, Semiconductor materials such as silicon, germanium, and gallium arsenide forms the germanium, and gallium arsenide forms the backbone of solid-state electronics that include backbone of solid-state electronics that include diodes, transistors, and integrated circuits. diodes, transistors, and integrated circuits.

With these, new electronics technology and With these, new electronics technology and applications are coming into existence together applications are coming into existence together with the rapid growth of multimedia with the rapid growth of multimedia communications in today’s society.communications in today’s society.

Uses of transistors: in amplifiers and in switching and control applications

DEVELOPMENT IN ELECTRONICS

The semiconductors together with The semiconductors together with software technologies brought tremendous software technologies brought tremendous development on media processing, development on media processing, connectivity (both wired and wireless), connectivity (both wired and wireless), automation and telephony.automation and telephony.

R & D in electronics tied up with other R & D in electronics tied up with other fields of study came up with robots, fields of study came up with robots, multimedia cellular phones, wireless LAN, multimedia cellular phones, wireless LAN, Bluetooth, GPS, 3G, hi-tech gadgets, etc…Bluetooth, GPS, 3G, hi-tech gadgets, etc…

The development of integrated The development of integrated circuits has revolutionized the fields circuits has revolutionized the fields of communications, information of communications, information handling, and computing. handling, and computing.

Integrated circuits reduce the size of Integrated circuits reduce the size of devices and lower manufacturing and devices and lower manufacturing and system costs, while at the same time system costs, while at the same time providing high speed and increased providing high speed and increased reliability.reliability.

..

Digital watches, hand-held computers, and Digital watches, hand-held computers, and electronic games are systems based on electronic games are systems based on microprocessors. Other developments microprocessors. Other developments include the digitalization of audio signals, include the digitalization of audio signals, where the frequency and amplitude of an where the frequency and amplitude of an audio signal are coded digitally by audio signal are coded digitally by appropriate sampling techniques, that is, appropriate sampling techniques, that is, techniques for measuring the amplitude of techniques for measuring the amplitude of the signal at very short intervals.the signal at very short intervals.

Digitally recorded music shows a fidelity Digitally recorded music shows a fidelity that is not possible using direct-recording that is not possible using direct-recording methods. Digital playback devices of this methods. Digital playback devices of this nature have already entered the home nature have already entered the home market. Digital storage could also form the market. Digital storage could also form the basis of home video systems and may basis of home video systems and may significantly alter library storage systems, significantly alter library storage systems, because much more information can be because much more information can be stored on a disk for replay on a television stored on a disk for replay on a television screen than can be contained in a bookscreen than can be contained in a book

In TELECOMMUNICATIONSIn TELECOMMUNICATIONSTelecommunications is the almost instantaneous transmission of sounds, words, data, pictures, and moving images by electronic means.

•Telephone System

•Communications Satellites

•Microwave Links

•Fiber Optic Link

•Mobile Phones

•Data Communications

•Internet

1G Mobile Telephone1G Mobile Telephone

Analog systemAnalog system Analog voiceAnalog voice Utilizes FM and high-power base Utilizes FM and high-power base

station controllersstation controllers Analog cellularAnalog cellular AMPS, NMT, TACSAMPS, NMT, TACS

2G Cellular2G Cellular

Digital systemDigital system Uses cellular conceptsUses cellular concepts Digitized voice and SMSDigitized voice and SMS GSM 900/1800/1900, DAMPS, GSM 900/1800/1900, DAMPS,

PDCPDC Data rate of 14.4 kbpsData rate of 14.4 kbps

2.5G Cellular2.5G Cellular High-speed circuit switched data High-speed circuit switched data

(HSCSD) –data transfer rate of 57.6 (HSCSD) –data transfer rate of 57.6 kbpskbps

General Packet Radio Service (GPRS)General Packet Radio Service (GPRS)---data services and applications ---data services and applications based on Internet Protocol to GSM based on Internet Protocol to GSM mobile networks (transfer rate of 35 mobile networks (transfer rate of 35 kbps)kbps)

MMS (multimedia messaging service)MMS (multimedia messaging service)

2.75G2.75G

Enhanced Data Rates for GSM Enhanced Data Rates for GSM Evolution (EDGE) ---- data rate of 384 Evolution (EDGE) ---- data rate of 384 kbpskbps

Faster connectionFaster connection Greater data volumes achievedGreater data volumes achieved Increase in functionalityIncrease in functionality Can interoperate w/ GSM network for Can interoperate w/ GSM network for

global coverageglobal coverage

3G Cellular3G Cellular

Universal Mobile Telecommunications Universal Mobile Telecommunications System (UMTS) is envisioned as the System (UMTS) is envisioned as the successor to GSMsuccessor to GSM

High data rates up to 2 MbpsHigh data rates up to 2 Mbps Used worldwideUsed worldwide For all mobile applicationFor all mobile application Streaming multimedia services such as Streaming multimedia services such as

video streamingvideo streaming Video calling and high-speed mobile Video calling and high-speed mobile

internet accessinternet access

BluetoothBluetooth

Enables compatible mobile devices, Enables compatible mobile devices, peripherals and computers that are peripherals and computers that are in close proximity to communicate in close proximity to communicate directly with each other without directly with each other without wires. (up to 10 m)wires. (up to 10 m)

Provides connectivity without Provides connectivity without network chargesnetwork charges

MMSMMS

A technology that allows you to A technology that allows you to create, send, and receive text create, send, and receive text messages that also include an messages that also include an image, audio, and/or video clips.image, audio, and/or video clips.

Sent from one mobile to another, or Sent from one mobile to another, or to an e-mail addressto an e-mail address

What is MECHATRONICS?The name Mechatronics stems from Mechanical and Electronics, and is a relatively new approach to product design and development, merging the principles of electrical, mechanical, computer, and industrial engineering. It addresses the four interconnected disciplines of used for all complex modern devices. Mechatronic systems are typically composed of traditional mechanical and electrical components, but are referred to as "smart" devices or systems because of the incorporation of sensors, actuators, and computer control systems.

WELCOME TO A DIGITAL WELCOME TO A DIGITAL ELECTRONIC WORLDELECTRONIC WORLD