Analog Electronics - 1 - May 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.

1 (a) Compare clipper and clamper circuit. (5 marks)

1 (b) Explain Barkhausen criteria for sustained oscillations. (5 marks)

1 (c) Compare Depletion and Enhancement type MOSFET. (5 marks)

1 (d) Transistor is a current controlled device while FET is a voltage controlled device. Justify. (5 marks)

2 (a) Define Stability factor. Derive the equation for stability factor. State which biasing technique is more stable. Justify your answer. (10 marks)

2 (b) For a NPN transistor in CE mode voltage divider bias configuration determine V_C and V_B-. Given V_CC=+20V, V_EE=-20V, R₁=8.2 KkΩ, R₂=2.2KΩ, R_C=2.7 KΩ, R_E=1.8 KΩ, C₁=C₂=10 7mu;F and β=120. (10 marks)

3 (a) Derive the equations for Av, Ai, Ri and Ro for a NPN transistor in CE mode voltage divider bias configuration with RE unbypassed. (10 marks)

3 (b) For the network given below determine Z_i, Z_o and A_v. (10 marks)

4 (a) Explain the basic operation and characteristics of n-channel enhancement type of MOSFET. (10 marks)

4 (b) Draw a neat circuit diagram of wien bridge oscillator and derive an expression for its output frequency, (10 marks)

5 (a) Determine IDQ, VGSQ VD & VS for the network given below: (10 marks)

5 (b) Determine Z_i Z_o & A_v for the circuit given below: (10 marks)

Write short note on any four:

6 (a) Biasing of JFET for Zero temperature drift. (5 marks)

6 (b) Energy band diagram of MOS capacitor. (5 marks)

6 (c) Small signal equivalent circuit of CC amplifier. (5 marks)

6 (d) Crystal oscillator. (5 marks)

6 (e) DC load line & significance of Q point. (5 marks)