ANALOG CIRCUITS For
ECE / EE / IN By
www.thegateacademy.com
Syllabus
Analog Circuits
Syllabus for Analog Circuits Small Signal Equivalent circuits of diodes, BJTs, MOSFETs and analog CMOS. Simple diode circuits, clipping, clamping, rectifier. Biasing and bias stability of transistor and FET amplifiers. Amplifiers: single-and multi-stage, differential and operational, feedback, and power. Frequency response of amplifiers. Simple op-amp circuits. Filters. Sinusoidal oscillators; criterion for oscillation; single-transistor and op-amp configurations. Function generators and wave-shaping circuits, 555 Timers. Power supplies.
Analysis of GATE Papers (Analog Circuits) Year
ECE
EE
IN
2013
15.00
8.00
18.00
2012
6.00
5.00
5.00
2011
10.00
5.00
15.00
2010
9.00
4.00
9.00
Over All Percentage
10.00%
5.50%
11.75%
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Contents
Analog Circuits
CONTENTS
#1.
#2.
Chapters Diode Circuits-Anaylsis & Application
Page No. 1 – 39
1 – 12 13 – 17 18 – 20 21 – 28 29 – 32 33 33 – 39
AC & DC Biasing-BJTs & FET
#3.
#4.
Wave Shaping Circuit Rectifiers and Power Supplies Solved Examples Assignment 1 Assignment 2 Answer Keys Explanation s
Operating Point BIAS Stabilization
Compensation Techniques Assignment 1 Assignment 2 Answer Keys Explanations
Small Signal Modeling Of BJT & FET
BJT Transistor Modeling The Hybrid Equivalent Model Characteristic of Common Base Amplifier FET Small signal Model. Assignment 1 Assignment 2 Answer Keys Explanations
BJT & JFET Frequency Response
Introduction Low Frequency Response –BJT Amplifier Low frequency Response –FET Amplifier Miller Effect Capacitance High Frequency Response –BJT Applfier High Frequency Response -FET Amplifier Assignment 1 Assignment 2 Answer Keys Explanations
40 - 87 40 – 46 46 – 55 55 – 66 67 – 73 74 – 78 79 79 – 87
88 – 136 88 – 94 94 – 99 99 – 105 105 – 114 115 – 121 122 – 126 127 127 – 136
137 – 169 137 – 139 139 – 142 142 – 144 144 – 147 147 – 149 149 – 155 156 – 160 161 – 164 165 165 – 169
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Contents
#5.
Feedback & Oscillator Circuits
#6.
Classification of Amplifier Feedback of Connection Types. FET Phase Shift Oscillator Wien Bridge Oscillator Solved Examples Assignment 1 Assignment 2 Answer Keys Explanations
Analog Circuits
170 – 210 170 – 173 173 – 178 179 180 – 188 189 – 194 195 – 199 200 – 204 205 205 – 210
Operational Amplifiers & Its Applications
211 – 291
211 – 212 212 – 214 214 214 – 223 223 – 240 241 - 243 244 - 254 255 – 260 261 – 265 266 – 274 275 – 280 281 281 - 291
Differential Amplifiers Analysis of Differential Amplifier Common Mode Rejection Ratio (CMRR) Operational Amplifier Practical Op-Amp Circuits Astable Multivibrator (Square Wave Generator) Zero-Crossing Detector The 555 Timer Solved Examples Assignment 1 Assignment 2 Answer Keys Explanations
#7. Power Amplifiers
Introduction Series –Fed Class Amplifer DC Bias Operation AC Operation Transformer Coupled Amplifier Push Pull Amplifier Transformer Coupled Push Pull Circuit Complementary –symmetry circuit Total Hormonic distrtion. Assignment 1 Assignment 2 Answer Keys Explanations
292 – 317 292 – 294 294 295 295 – 298 298 – 299 299 – 301 301 301 – 305 305 – 306 307 – 311 311 – 312 313 313 – 317
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Contents
Module Test
Test Questions Answer Keys Explanations
Reference Books
Analog Circuits
318 – 345 318 – 335 336 336 – 345
346
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Chapter-1
Analog Circuits
CHAPTER 1 Diode Circuits - Analysis and Application Wave Shaping Circuits Wave shaping circuits are of two types (A) Linear wave shaping circuits (B) Non linear wave shaping circuits A. Linear Wave Shaping Circuits The process by which the wave form of non sinusoidal signal is altered by passing it through the linear network is called the linear wave shaping High Pass Circuit
C +
+ Vi R
Vo
-
-
Fig. 1 High Pass Circuit This circuit is called the high pass filter because it passes the high frequency components and attenuates the low frequency components. For low frequency, the reactance of the capacitance is large (a) Sinusoidal input:
(
) (
| | √
)
(
)
( ⁄)
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Chapter-1
|
Analog Circuits
|
1 0.707
Fig. 2 Gain-frequency plot of high pass circuit (b) Step Input: () V
0
Fig. 3 Output voltage of high pass circuit when input is a step voltage = () = 1/C iR, So ( ) 1/RC
()
(t) ()
() ()
(t) dt +
()
()
()
It is a single time constant circuit and a first order equation is obtained. The general solution of any single time constant circuit can be written as, ()
(
(c) Pulse Input:
) ()
, here Vf = 0, Vi = V, Vo(t) = Ve- τwhere τ [ ()
(
)]
1) (
2)
)
τ τ
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Chapter-1
Analog Circuits
( ) V 1
0
2
Fig. 4 Output of high pass filter, when input is a pulse For a low time constant the peak – to – peak amplitudes will be double. The process of converting pulses into spikes by means of a low time constant is called peaking. In high pass RC circuit, the average level of the output is always zero. The area above the zero axis should be equal to the area below the zero axis, A1 = A2 (d) Square Wave Input For a non-symmetrical square wave Case 1: τ
τ
,
+
= T = 1/f. The extreme cases are
The input and output are shown below,
(a) Average voltage
Zero voltage
(b) V0 A1
0
Zero voltage
V
t
A2 T1
T2
T1
T
Fig: 5 (a) Square wave input; (b) Output voltage if the time constant is very large (compared with T). The dc component V d –c of the output is always zero. Area A1 equals area A2.
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Chapter-1
Case 2: τ
τ
Analog Circuits
The response is shown below;Note: 5(a) Square wave input V0 Input V 0
t V
T1
T2 T
Fig: 6 Peaking of a square wave resulting from a time constant small compared with T. More generally the response to a square wave must have the appearance shown below: The four levels V1, V1’
2,V2’
can be determined from (refer figure 7)
For symmetrical square wave: T1 = T2 = T/2 ’ P c
‘P’
P= =
and the response is shown below in Fig. 7(b)
100
by 100 %
100 %
Where f1 =
and
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Chapter-1
Analog Circuits
t
(
)
( )
Output
Input
t
(b)
Fig. 7 Linear tilt of a square wave when RC/T >> 1. (e) Ramp Input: Vi(t) = Signal
t u (t) and Vo(t) =
τ (1
), are shown below,
Input = Output
Deviation from Linearity Output
0 Fig (a)
T
t
0
T
t
Fig (b)
Fig. 8 (a) Response of a high pass RC circuit to a ramp voltage for RC / T >> 1; (b)Response to a ramp voltage for RC / T << 1. For t <<τ as a measure of departure from linearity, transmission error, et is defined as
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