# RGPV Exams Questions Papers – 3rd SEM. – Dec- 2007, Electronics

B.E. (Third semester) EXAMINATION, Dec. 2007

(Common for EC/EE/EX Engg.)

(ELECTRONIOCS)

(CS/EE/IP-304)

Note:      Attempt any five questions in all. Attempt one question from each unit. Assume suitable data

missing data if any.

1. (a)    Give V-1 characteristics of P-N diode and explain the same with forward and reserve biasing of

the device.

(b) What is Zender diode? How is it different from the a P-N junction diode ? Explain with different

breakdown mechanism of BJT.

2. (a) What are the different operating regions of a BJT ? Explain .Also give amplification of BJT.

(b)  Explain the following:

(i) Biasing of BJT                   (ii) Q-point

3. (a) Discuss biasing techniques for BJT in brief.

(b)    An amplifier is shown in fig.1. Calculate the output voltage for input voltage of 1mV (r.m.s.)

assuming that B=80 and Rin  =2K .

4. (a) Define h-parameters for BJT . Determine voltage and current gain in terms of h-parameters for BJT

at low frequency .

(b)  Calculate the current and voltage gain of a CE amplifier having the following g parameters.:

Hie = 1100 ohm,  hre =2.5 × 10-4 , hfe  = 50,

Hoe = 25 × 10-6 mho, Rs = 1k-ohm, RL = 1 k ohm.

5. (a) What re the four feedback configuration ? Explain and define feedback factor.

(b)  Draw the circuit diagram of an emitter follower and discuss about the feedback mechanism

employed herein.

6. (a) Give the classification of power amplifiers .

(b)  What is Wien bridge oscillator ? Explain and derive expression for frequency of oscillator.

7. (a) Analysis the switching action of BJT.

(b)  What is astable multavibrator ? Explain

8. (a) What is differential amplifier ? Explain and define its basic parameters of analysis.

(b) What is boot strapping ? Explain

9. (a) Give the characteristics of an ideal OP-AMP  and explain.

(b) What is summing OP-AMP amplifier? Give its analysis.

10. (a) Determine the voltage gain of an OP-AMP instrumentation amplifier .

(b) What is Schmitt trigger ? Explain