Discrete Electronic Circuits - May 2015

Electronics Engineering (Semester 4)

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.

Solve any four:

1 (a) Implement appropriate circuit to generate following waveform. (5 marks) 1 (b) Draw small signal equivalent circuit of CS amplifier with voltage divider bias.(5 marks) 1 (c) Explain need for cascading of amplifiers.(5 marks) 1 (d) State and explain Barkhausen criteria.(5 marks) 1 (e) Derive efficiency of Class A transformer coupled amplifier.(5 marks) 2 (a) For the given circuit determine Zi, Zo, Av. (10 marks) 2 (b) For the given circuit find Idq and VGSq. Also state in which operating region circuit works. (10 marks) 3 (a) Draw and explain working of cascode amplifier.(10 marks) 3 (b) For the given differential amplifier determine Icq, V_CEq, AD and Acm. (10 marks) 4 (a) Explain working of Wien-Bridge oscillator and give expression for frequency of oscillation.(10 marks) 4 (b) Draw block diagram of voltage shunt -ve feedback amplifier and explain effect on i/p impedance, o/p impedance and gain.(10 marks) 5 (a) For the E-MOSFET amplifier determine, Ri, Av & Ro. (10 marks) 5 (b) Explain class B power amplifier and methods to remove cross over distortion.(10 marks)

Write short note on (any two):

6 (a) Constant current source used in differential amplifier. (Wildar or Wilson type).(10 marks) 6 (b) Crystal oscillator(10 marks) 6 (c) Power MOSFETs.(10 marks) 6 (d) Heat Sinks.(10 marks)