Department of Physics - Dr.Zahir Husain College, Ilayangudi
Analog Electronics – 1BPH5C1
Time: 3 Hours Max Marks: 75
Part – A (10 x 2 = 20)
Answer All the Questions
1. How diode acts as a rectifier?2. Draw the special current-voltage characteristics of Zener diode.
3. Why the collector region is larger than the emitter region in a transistor?
4. Write brief note on transistor action.
5. Draw the circuit diagram of single stage amplifier circuit.
6. Define band width.
7. State any two differences between voltage and power amplifiers.
8. Write note on feed back.
9. List out the characteristics of an ideal op-amp.
10. Draw the circuit diagram of a non-inverting amplifier.
Part – B (5 x 5 = 25)
Answer All the Questions
11. Discuss the working of a half wave rectifier.(OR)
Discuss the formation of depletion layer in PN junction.
12. Write note on cut-off and saturation point.
(OR)
Describe the feedback resistor method of biasing a transistor.
13. Draw the DC equivalent circuit of a transistor amplifier and explain its function.
(OR)
Explain RC coupling in a multistage amplifier.
14. Explain the phenomenon of phase reversal in a transistor amplifier.
(OR)
Write note on class A amplifier.
15. Discuss the working of an op-amp adder.
(OR)
How an op-amp is used as a triangular wave generator?
Part – C (3 x 10 = 30)
Answer any three Questions
16. (a)Describe the function of Zener diode as a voltage regulator.(b)Derive an expression for the efficiency of bridge rectifier.
17. (a)Compare CE,CB and CC transistor configurations.
(b)Write note on load line.
18. (a)Describe the function of direct coupled multistage amplifier.
(b) In an amplifier, the maximum voltage gain is 2000 and occurs at 2 kHz. It falls to 1414 at 10 kHz and 50 Hz. Find : (i) Bandwidth (ii) Lower cut-off frequency (iii) Upper cut-off frequency.
19. a)Explain the function of Colpitts oscillator.
(b) Find the capacitance of the capacitor required to build an LC oscillator that uses an inductance of L= 1 mH to produce a sine wave of frequency 1 MHz.
20. (a)Explain how an op-amp is as an integrator and scale changer.
(b)Feedback resistor of an inverting amplifier has the value of 100 k ohm and the input resistor has the value of 2 k ohm. If a sinusoidal wave of peak-to-peak voltage 50 mV is given as input plot the output wave form.