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LOYOLA COLLEGE (AUTONOMOUS), CHENNAI 600 034
B.Sc.DEGREE EXAMINATION -PHYSICS
THIRD& FIFTH SEMESTER APRIL 2018
PH 3504 PH 3502 PH 5501- ELECTRONICS I
Date: 05-05-2018 Dept. No. Max. 100 Marks
Time: 01:00-04:00
PART-A
Answer ALL the questions (10x2=20 Marks)
1. State Thevenin's Theorem.
2. What is a constant voltage source?
3. Write the different methods of transistor biasing.
4. What is a monostablemultivibrator?
5. Draw the equivalent circuit of UJT.
6. A difference amplifier has a differential voltage gain of 2000 and a common mode gain of 0.2.Calculate CMRR and write it in dB.
7. What is the function of a multiplexer?
8. Draw the logic diagram and write the truth table of a D flip-flop.
9. What is a ripple counter?
10. Write any two differences between ROM and RAM.
PART-B
Answer Any Four questions (4x7.5=30Marks)
11. State the maximum power theorem and derive the condition for transfer of maximum power from
source to a load.(2.0 5.5)
12.(a) Explain the working of a phase shift oscillator with a neat circuit diagram.
A phase shift oscillator uses 5pF capacitors. Find the value of R to produce a frequency of
800 kHz.
13.With relevant circuit diagrams, explain the operation of OP-AMP as summing and difference
amplifier. (3.5+4.0)
14.Describe the function of a 7 segment decoder with a neat diagram.
15. Explain the working of three bit binary ripple counter using JK flip flop.(7.5)
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PART-C
Answer Any Four questions (4x12.5=50)
16. Obtain expressions for the input impedance, current gain, voltage gain and output impedance in
terms of h-parameters using the equivalent circuit of a transistor in CE configuration.
17. With necessary circuit explain the construction and working of a Bistablemultivibtator.(5.0+7.5)
18. Describe the construction and working of a silicon controlled rectifier. With circuit diagram,
explain how it acts as a half wave rectifier. (7.5+5.0)
19. Explain the operation of JK flip flop and JK Master Slave flip-flop with their logic diagrams
and truth tables. (6.5+6.0)
20) With neat circuit diagrams, explain the function of shift left and shift right shift registers.
(6.5+6.0)