1
Seat No.: Enrolment
GUJARAT TECHNOLOGICAL UNIVERSITY
PDDC SEMESTER-III EXAMINATION WINTER 2018
Subject Code:X31101 Date: 17/11/2018
Subject Name: Advance Electronics
Time: 10:30 AM TO 01:30 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

Obtain the expression for voltage gain, input and output impedance of Emitter Follower amplifier using BJT.
07

Draw The Hybrid model for CE configuration and explain it. Derive the equation for any two parameters those affecting to the transistor at high frequencies for CE configuration
07
Q.2

Draw the circuit diagram of current series feedback with transistor and derive the expression for gain, input resistance and output resistance
07

Draw and Explain two stages cascaded amplifier and derive its equation for
Voltage gain.
07
OR

Explain Frequency Response of An Amplifier. Discuss in brief High Frequency and Low frequency Response.
07
Q.3

List out the compensation techniques for stability of amplifiers. Explain with suitable diagram any two of them.
07

With the help of a neat sketch, for an underdamped two-pole amplifier response, define rise time, delay time, overshoot, damped period, settling time.
07
OR
Q.3

The output impedance may be calculated as the ratio of open-circuit voltage to
the short-circuit current. Using this method, evaluate Rof for all the four feedback topologies.
07

Describe the effect of negative feedback on amplifier bandwidth.
07
Q.4

State and explain the Nyquist stability criterion.
07

For an non-inverting amplifier R1=1 kΩ and Rf=10kΩ. The Parameters of OP-AMP are as follows: Av=2x105, Ri=2MΩ, R0=75Ω, f0=5 Hz. If the supply voltages are limited to ±15 V and output voltage swing is ±13 V compute the values of Avf, Rif Rof and fF.
07
OR
Q.4

Define CMRR. Explain the significance of CMRR. List out the method to improve the CMRR and explain any one of them.
07

Sketch the circuit of a Wien bridge oscillator. What determines the frequency of oscillation?
07
Q.5

Explain the difference of Dominant pole compensation, Pole zero compensation and Lead compensation.
07

What is Digital to Analog converter? Give the applications of D/A converters. Explain R-2R DAC.
07
OR
Q.5

Define the following terms regarding logic family:
Noise margin Fan In Fan Out Propagation delay
07

Explain the operation of Dual Slope ADC and state its advantages.
07