EEE C364 / INSTR C364

Analog Electronics

In this course-

OP-AMP basicsSpecial purpose OP-AMP circuitsActive FiltersNon-linear OP-AMP circuitsSignal Sources & Phase lock loopVoltage RegulatorsIC Power AmplifiersTuned AmplifiersData Converters-D/A, A/D ConvertersIC sensors and Analog Systems

List of experiments: (TB2)

1. Common Emitter Amplifier (Exp.2)

2. High Input Resistance Transistor Amplifier (Exp.3)

3. Basic Configuration of OPAMP (Exp.5)

4. Study of Feed Back Amplifiers Using OPAMPs (Exp. 8)

5. Instrumentation and Programmable Amplifier (Exp.7 )

List of experiments: (Contd)

6. Study of Active Filters Using OPAMPs --LP, HP,BP

(Exp.9 )

7. Precision Circuit (Exp.12)

8. Sinusoidal and Non-Sinusoidal Oscillators (Exp.15)

9. Integrated Circuit Timer and Phase Locked Loop

(Exp.16, Exp.17)

10. IC Fixed and adjustable Voltage Regulators (Exp.19)

Evaluation Components:Test-I ------- 40 M

Test-II ------- 40 M

Tutorials ------- 40 M

Library Assignment I ------ 10 M

Assignment II -------- 10 M

(Laboratory Computer Simulation /Circuit Fabrication )

Experiments Day/Day ------- 30 M

Laboratory Test ---------- 30 M

Comprehensive -------- 100 M

INTRODUCTION:Electronic System:

This system measures unknown weights

Indicates the weights by measuring the proportional dc current in a permanent magnet moving coil (PMMC) meter.

RRncompressioGRRextentionG

+

2

1

RR

VRRR

VV SSo 2][

2=

RRVV So

=

2||

Inverting Amplifier, with Rin=

)](||)[()||( RRRRRRRth ++=

Thermocouple: (-200 oC to 2300 oC)

Thermocouple is created whenever two dissimilar metalstouch and the contact point produces a small open-circuit voltage as a function of temperature.

e.g. Platinum Rhodium Platinum, Copper -Constantan

This thermoelectric voltage is known as the Seebeckvoltage, named after Thomas Seebeck, who discovered it in 1821.

Commonly found in engines and burners

TSV =Where:

V :change in voltage

S : Seebeck coefficient

T :change in temperature

Resistance temperature detectors (RTDs): T,R (-100 oC to 800 oC)

operate on the principle of changes in the electrical resistance of pure metals.

These are characterized by a linear positive change in resistance with temperature.

e.g. nickel (Ni) , copper (Cu) and platinum (Pt)

A high electrical output can be obtained by using the RTD with many types of simple resistance bridges.

Resistance Thermometers can be used for a wide variety of industrial applications

Thermistors: (-20 oC to 150 oC)

A thermistor is an electronic component that exhibits a large change in resistance with a change in its body temperature.

Applications: air conditioning, electronics, refrigeration

It can have large positive temperature coefficient of resistance (PTC)large negative temperature coefficient of resistance

(NTC).

Piezoelectric sensors:

Piezoelectric sensors convert force to voltage

The piezoelectric effect: some crystalline materials (e.g. quartz) generate a small voltage when they are distorted.

Used to measure force, pressure or acceleration

(Vacuum or Ambient)

Integration of transducers on chip

e.g. AD590 (1A/0K)

Integrated Circuit (IC) Sensors consist of:

Silicon semiconductor sensor or silicon micro transducers (SMTs)

as well as signal processing

Mechanical elements along with electronic circuits are currently being integrated into silicon substrate:

micro electro mechanical systems (MEMS).

Signal Frequency Range:

Microphone: 500Hz-12kHz

Temperature: 0.01Hz 20Hz

Biomedical equipments: 0.001 Hz to 10Hz

Electrical output Range:

Industrial Standard Output for instruments ( 4mA-20mA transmitters)

Pressure Reading

3psi 15psi4mA 20mA

Voltmeter:

Case 1: Calculate the error in Measurement voltage across R2by a voltmeter having internal resistance of 100K.

VVKRKR

VVLet

50100&100

,100,

2

21

===

=

%34.3310050

33.3350%

33.3310015050

:

=

=

=

VVVerror

VKK

eadingRVoltmeter

If voltmeter have internal resistance of value then it doesnt load source.

Case2: Calculate the error in measurement voltage across R2by a voltmeter having internal resistance of 1M .

VVKRKR

VVLet

50100&100

,100,

2

21

===

=

%78.410050

61.4750%

61.4710090.19090.90

:

=

=

=

VVVerror

VKK

eadingRVoltmeter

Electronic instruments (EVM) should have high input resistance (1M)

Signals and Sources

2

1

)(

21

0

2)(

mrmsS

T

srmsS

VV

dtvT

V

=

=

+++= ...5sin

513sin

31sin4)( 000 ttt

VtV m

Signal sources

Independent sources.

Dependent sources.

=

=LRi

V VVA 00

0

0

=

=LRi

is IIA

=

=LRi

m IVR 0

0

0

=

=LRi

m VIG

i

oisv

oiisiiv

iii

oiisiv

RRAA

RiAiRAiRv

RiAvA

=

==

=

0

0

0

omv RGA =0

i

mv

imiiv

imiv

RRA

IRIRAIRVA

=

==

0

0

0

)(

KVL

KCL

Thvenins Theorem

Nortons Theorem

Maximum Power Transfer Theorem

Superposition Theorem

Millers Theorem

Nodal analysis

Mesh analysis

BASIC DEVICES

Diodes Ideal Diodes

Practical diode

Zener diode

BJT

FET JFET

MOSFET

MESFET

OPAMP

Types of Feedback

ELECTRONIC CIRCUITS ANALYSIS AND DESIGN1. Definition of specifications/requirements of the system

2. Identifying the functional blocks/circuits

3. Definition of specifications for individual functional blocks/circuits

4. Integration of functional blocks into the desired system

5. Simulation or modeling

6. Testing and verification.

Design Center Activities:

Foundrys Activities:

Amplifier circuit Symbol operated by two power supplies:

Linear Amplifier (operated by two power supplies) except for output saturation

L-/Av vI L+/Av

Non Linear Transfer characteristics and Biasing using single power supply.

Quiescent means no signal condition

Non-linear distortion in Linear Amplifier:

Non linearity generates the frequency in multiplies of input. Itis called harmonic distortion or non-linear distortion

tvAtvAtvAv

tvvwherevAvAvAv

mmmo

mI

IIIo

33

322

21

33

221

coscoscos

cos,

++=

=++=

tBtBBvtBBtBv

tvAtvAv

oo

oo

mmo

2coscos2coscos

)2cos1(2

cos

21

21

2

21

++=++=

+=

Considering only two terms:

Non linear distortion in Linear Amplifier:

223

22

1

33

1

22

......

%100*

%100*

nDDDTHDD

distortionhormonicThirdBB

D

distortionhormonicecondsBB

D

++==

=

=

Differential pair or differential amplifier:

Basic Building Block in analog integrated Circuits.

Input stage of every OP-AMP is a differential amplifier.

Why Differential? (Advantages over single-ended)

Differential circuit are much less sensitive to noise and interference than single-ended circuits. (difference between the two wires is sensed, therefore it will eliminate interference component)

Differential amplifier configurations enable us to bias and to couple amplifier stages without the need for bypass and coupling capacitors as used in discrete-circuit amplifiers.