Download GTU (Gujarat Technological University) BE/BTech (Bachelor of Engineering / Bachelor of Technology) 2018 Winter 4th Sem New 2141002 Analog Circuit Design Previous Question Paper
1
Seat No.: ________ Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY
BE - SEMESTER ?IV (NEW) EXAMINATION ? WINTER 2018
Subject Code:2141002 Date:22/11/2018
Subject Name:Analog Circuit Design
Time: 02:30 PM TO 05:00 PM Total Marks: 70
Instructions:
1. Attempt all questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
Q.1 (a) State the functions of the transistors connected to the reset and discharge
pins of IC 555.
03
(b) What is the role of the inter electrode capacitances Cbc, Cbe and Cce in a
hybrid ? model? Why Cce does not figure in the model?
04
(c) Define the following for an Op Amp:
[1] Input Resistance [2] Slew Rate [3] Balanced output [4]
PSRR
[5] Voltage Gain [6] Offset Voltage [7] Unity Gain Bandwidth
07
Q.2 (a) A bipolar junction transistor has hie=1 K?, hfe= 100; hre , hoe are negligible.
Cc=3pF and the collector current is 10mA. The short circuit current gain is
10 at a frequency of 10 M Hz. Calculate the values of f?, f? and f?.
03
(b) List all the resistances and their typical values in a hybrid ? model 04
(c) Draw the hybrid ? model for a single stage CE transistor amplifier having
load resistance RL and obtain the expression for short circuit current gain.
07
OR
(c) Draw the hybrid ? model for a transistor in CE configuration and derive
the expression for transconductance gm. Justify the validity of this model.
07
Q.3 (a) Perform DC analysis of a Dual Input Balanced Output Differential
Amplifier
03
(b) For a given operational amplifier, the input voltages are 150 ?V and 140
?V DC. This amplifier has a differential gain of 4000 and a CMRR of 100.
Evaluate its output voltage. What change would occur in its output voltage
if the CMRR changes to a new value of 1,00,000 ?
04
(c) Define CMRR. Discuss the effect of RE on CMRR. How can a constant
current source and a current mirror circuit help to improve this value?
07
OR
Q.3 (a) For a dual input balanced output, it is given that VCC= +12V, RC=4.7 K?,
RB= 100? and RE= 2.7 K?. Evaluate its Quiescent point of operation.
03
(b) What is the significance of Slew Rate? How does it affect the performance
of an Op Amp?
04
(c) Explain the working of an adder and a Subtractor circuit to perform the
mathematical operation VO=V1+V2 and VO=V1-V2 respectively.
07
Q.4 (a) What are precision rectifiers? Explain the working of anyone of them. 03
(b) How does the working of an operational amplifier differ in inverting and
noninverting configurations?
04
(c) Discuss op amp based triangular waveform generator circuits. Obtain the
expression for the same.
07
OR
www.FirstRanker.com www.FirstRanker.com
www.FirstRanker.com
FirstRanker.com - FirstRanker's Choice
www.FirstRanker.com
1
Seat No.: ________ Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY
BE - SEMESTER ?IV (NEW) EXAMINATION ? WINTER 2018
Subject Code:2141002 Date:22/11/2018
Subject Name:Analog Circuit Design
Time: 02:30 PM TO 05:00 PM Total Marks: 70
Instructions:
1. Attempt all questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
Q.1 (a) State the functions of the transistors connected to the reset and discharge
pins of IC 555.
03
(b) What is the role of the inter electrode capacitances Cbc, Cbe and Cce in a
hybrid ? model? Why Cce does not figure in the model?
04
(c) Define the following for an Op Amp:
[1] Input Resistance [2] Slew Rate [3] Balanced output [4]
PSRR
[5] Voltage Gain [6] Offset Voltage [7] Unity Gain Bandwidth
07
Q.2 (a) A bipolar junction transistor has hie=1 K?, hfe= 100; hre , hoe are negligible.
Cc=3pF and the collector current is 10mA. The short circuit current gain is
10 at a frequency of 10 M Hz. Calculate the values of f?, f? and f?.
03
(b) List all the resistances and their typical values in a hybrid ? model 04
(c) Draw the hybrid ? model for a single stage CE transistor amplifier having
load resistance RL and obtain the expression for short circuit current gain.
07
OR
(c) Draw the hybrid ? model for a transistor in CE configuration and derive
the expression for transconductance gm. Justify the validity of this model.
07
Q.3 (a) Perform DC analysis of a Dual Input Balanced Output Differential
Amplifier
03
(b) For a given operational amplifier, the input voltages are 150 ?V and 140
?V DC. This amplifier has a differential gain of 4000 and a CMRR of 100.
Evaluate its output voltage. What change would occur in its output voltage
if the CMRR changes to a new value of 1,00,000 ?
04
(c) Define CMRR. Discuss the effect of RE on CMRR. How can a constant
current source and a current mirror circuit help to improve this value?
07
OR
Q.3 (a) For a dual input balanced output, it is given that VCC= +12V, RC=4.7 K?,
RB= 100? and RE= 2.7 K?. Evaluate its Quiescent point of operation.
03
(b) What is the significance of Slew Rate? How does it affect the performance
of an Op Amp?
04
(c) Explain the working of an adder and a Subtractor circuit to perform the
mathematical operation VO=V1+V2 and VO=V1-V2 respectively.
07
Q.4 (a) What are precision rectifiers? Explain the working of anyone of them. 03
(b) How does the working of an operational amplifier differ in inverting and
noninverting configurations?
04
(c) Discuss op amp based triangular waveform generator circuits. Obtain the
expression for the same.
07
OR
www.FirstRanker.com www.FirstRanker.com
www.FirstRanker.com
www.FirstRanker.com
2
Q.4 (a) For IC 555, explain the functions of the following pins:
[1] Trigger [2] Threshold [3] Control
03
(b) What is thermal drift and error voltage? Suggest methods to reduce the
same.
04
(c) Explain the compensation of input offset voltage with a neat diagram. 07
Q.5 (a) Draw the block diagram of PLL and explain each block. 03
(b) Discuss the features of LM317 Regulator. 04
(c) Derive expression of frequency of oscillation of an RC phase shift
oscillator.
07
OR
Q.5 (a) Derive the expression for filter transfer function of a first order low pass
filter and draw its frequency response characteristics.
03
(b) Discuss any one application of a PLL in modulation signal detection. 04
(c) Derive expression of frequency of oscillation of a Wein Bridge oscillator. 07
*************
www.FirstRanker.com www.FirstRanker.com
www.FirstRanker.com
FirstRanker.com - FirstRanker's Choice
This post was last modified on 20 February 2020