Analog Electronics - 1 - Dec 2015
Electronics & Telecomm. (Semester 3)
TOTAL MARKS: 80
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any three from the remaining questions.
(3) Assume data if required.
(4) Figures to the right indicate full marks.
Attempt any four:
1 (a) Draw Input and Output characteristics of BJT in common emitter configuration.(5 marks) 1 (b) Draw small signal hybrid π equivalent circuit for npn transistor.(5 marks) 1 (c) Explain effect of temperature on JFET and derive equation for zero current drift.(5 marks) 1 (d) Calculate IB, IC & VCE for common emitter circuit. (5 marks) 1 (e) Find IB, IC & VCE for following circuit. (5 marks) 2 (a) Draw output waveform for clamper and clipper circuits.
(ii)(10 marks) 2 (b) Explain construction & characteristics of n channel Enhancement MOSFET. Draw transfer characteristics & drain characteristics.(10 marks) 3 (a) For JFET amplifier shown below, Calculate Av, Zi, Zo. (10 marks) 3 (b) For the circuit shown below, calculate IDQ & VDSQ. It is given that ID(ON)=6 mA, VGS(ON)=8V. Vth=3V. (10 marks) 4 (a) Explain the working of Wein Bridge Oscillator. Derive the expression for frequency of oscillation for sustained oscillations.(10 marks) 4 (b) Calculate voltage gain of FET amplifier.
VGS off=-4V (10 marks) 5 (a) Draw & explain energy band diagram of MOS capacitor operating in
iii) Inversion mode(10 marks) 5 (b) Draw emitter follower circuit and derive an expression for voltage gain Av.(10 marks) 6 (a) Draw circuit diagram for phase shift oscillator & derive an expression for frequency of oscillation.(10 marks)
Write short notes on any two:
6 (b) (i) Photodiodes(5 marks) 6 (b) (ii) LC Oscillators(5 marks) 6 (b) (iii) Transistor as a switch(5 marks) 6 (b) (iv) Schottky diode(5 marks)