Periyar University 2006 B.Sc Electronics ELECTRONIC CIRCUITS - Question Paper

Third Semester
Electronics
ELECTRONIC CIRCUITS
Time : 3 hours Maximum : 100 marks
part A — (10 x two = 20 marks) ans ALL ques..
1. Knee voltage of a silicon diode is (a) 0.3 V (b) 0.6 V (c) 0.1 V (d) 1.6 V.
2. V =
ave
(a) -^ (b) 2Vm
•v2 n
(C) ^V^ VjrJL
n V2 *

3. Operating point is also known as
(a) Quiescent point (b) Quality factor
(c) Curie point (d) Boiling point.
4. Thermal stability can be achieved using
(a) Self biasing
(b) Fixed biasing
(c) Voltage divider biasing
(d) Base biasing.
5. Pinch off voltage is related to
(a) Transistor (b) Diode
(c) JFET (d) PUT.
6. FET operation can be compared with (a) DIODE (b) TRIODE (c) Pentode (d) Hexode.
7. Push pull amplifier generates

(a) Cross over distortion
(b) Harmonic distortion
(c) Chrono discharge
(d) Low frequency noise.

8. Stability of an amplifier can be improved by
(a) Positive feed back
(b) no feed back
(c) negative feed back
(d) none of the above.
9. Frequency of oscillation of Wien bridge oscillator is
t \ X ru\ L44
(a) . (b) ==

(c) -= j= (d)
<42TC4RC 2n^RxR2
10. r] stands for
(a) intrinsic stand of Ratio
(b) ripple factor
(c) firm factor
(d) gain of amplifier.
part B — (5 x six = 30 marks) ans ALL ques..
11. (a) discuss the working of Fullwave rectifier.
Or (b) Write a note on IC voltage regulator.
12. (a) discuss the Drain Resistance, Mutual
conductance amplifying factor in JFET.
Or
(b) Compare CE, CB and CC configurations.
13. (a) discuss the working of transistor.
Or (b) What is quiescent point? discuss.
14. (a) What is bandwidth of an amplifier? discuss.
Or
(b) explain the effect of negative feedback in amplifier.
15. (a) With a neat diagram, discuss the working of
Hartley oscillator.
Or
(b) Write a note on frequency stabilization in oscillator.
part C — (5 x 10 = 50 marks) ans ALL ques..
16. (a) discuss the VI characteristics of Zener Diode. \lso discuss the working of zener voltage regulator.
Or
(b) discuss (i) RMS voltage (ii) avg. voltage I iii) Ripple factor (iv) Rectification efficiency.
17. (a) Briefly explain about CE configuration and
discuss the use of DC bias with emitter resistor.
Or
(b) discuss in detail about H-parameters.
18. (a) With neat diagram discuss the fixed bias and
voltage divider bias circuits.
Or
(b) discuss in detail about common source amplifier design.
19. (a) Briefly explain about Push pull amplifier and its advantages and distortions.
Or
(b) discuss the feed back in amplifier and kinds of feedback in detail. Also find expression for its voltage gain.
20. (a) Mention the kinds of LC oscillators and discuss the working -of any 2 kinds.
Or
(b) With neat diagram, discuss the working of UJT relaxation osciLllator. find an expression for its output frequency. Wlhat is the importance of RE in UJT Relaxation Oscillator?

Earning:   Approval pending.