1. SUBJECT: ELECTRONIC CIRCUITS LAB Subject Code: EC-306
Class/Semester: II/III Number of Students: 45
Faculty Name: K SAKRU NAIK Designation: Asst Professor
Department: ECE
VIVA Questions
1. Define knee voltage of a diode.
2. Draw VI characteristics of pn junction diode.
3. Although zener diode is operated in the reverse breakdown region, but it does not burn. Why?
4. Differentiate between static and dynamic resistance of a diode.
5. Differentiate between avalanche and zener breakdown.
6. Draw the VI characteristics of an ideal diode.
7. Draw the circuits of CB, CE and CC configurations using npn transistor.
8. What do you understand by Operating point?
9. Why do we choose the Q point at the center of the load line?
10. Name the two techniques used in the stability of the q point .explain.?
11. Define stability factor &Give the expression for stability factor?
12. List out the different types of biasing.
13. What do you meant by thermal runway?
14. Why transistor is called as a current controlled device?
15. Define current amplification factor?
16. What are the requirements for biasing circuits?
17. When does a transistor act as a switch?
18. What is biasing?
19. What is an operating point?
20. What is d.c load line?
21. Explain about the various regions in a transistor?
22. Explain about the characteristics of a transistor?
2. 23. Why the operating point is selected at the Centre of the active region?
24. What is an amplifier?
25. What is small signal amplifier?
26. What is a Darlington pair?
27. Define Common Mode Rejection Ratio.
28. What is meant by Differential Amplifier?
29. What do you mean by balanced and unbalanced output?
30. What are the methods of improving CMRR?
31. Give few applications of differential amplifier
32. What is the necessity of heat sink?
33. Compare the features of the three transistor configurations.
34. Compare the features of the three transistor configurations.
35.Why is base made thin and lightly doped?
36. Explain why an ordinary transistor is called bipolar.
37. Why is transistor called a current controlled device ?
38.Why is collector region is greater than emitter region?
39. Draw the basic structure of an N channel junctionfield effect transistor.
40. Why is FET known as a unipolar device?
41. What are the advantages and disadvantages of JFET over BJT?
42. What is a channel?
43. Distinguish between JFET and MOSFET.
44. What is an effect of cascading?
45. What are all the factors affecting the bandwidth of the RC
46. Coupled amplifier?
47. Explain bypass capacitor?
48. What is meant by coupling capacitor?
49. Why does amplifier gain reduce?
50. Explain the different regions in frequency response?
51. State the types of distortions in amplifier?
52. What is cross over distortion? How it can be eliminated?
53. Define noise?
3. 54. Define step response?
55. Draw the symbol of JFET and MOSFET.
56. What are the two modes of MOSFET?
57. Define pinch-off voltage
58. What is feed back and what are feed back amplifiers?
59. What is meant by positive and negative feedback?
60. What are the advantages and disadvantages of negative feed back?
61. Differentiate between voltage and current feedback in amplifiers?
62. Define sensitivity?
63. Define De-sensitivity?
64. What is the type of feedback used in an op- amp Schmitt trigger?
65. Give the expression for the frequency of oscillations in an op-amp sine wave
66. oscillator?
67. What are the conditions for sustained oscillator or what is Backhouse criterion?
68. What is Oscillator circuit?
69. What are the classifications of Oscillators?
70. What are the types of feedback oscillators?
71. Define Piezo-electric effect?
72. Draw the equivalent circuit of crystal oscillator?
73. What is Miller crystal oscillator? Explain its operation?
74. State the frequency for RC phase shift oscillator?
75. Give the topology of current amplifier with current shunt feedback?
76. What are gain margin and phase margin?
77. What is the minimum value of hfe for the oscillations in transistorized RC
78. Phase shift oscillator?
79. What is LC oscillator?
80. Draw the circuit of clapp oscillator?
81. How does an oscillator differ from an amplifier?
82. Name two low frequency oscillators?
83. What is class AB operation?
84. Define conversion efficiency of a power amplifier. What is its value for class C
4. 85. power amplifier?
86. What is crossover distortion? How it can be eliminated?
87. What is meant by Harmonic distortion?
88. What is the drawback of class B amplifier? How is this minimized?
89. Define thermal resistance in the context of power amplifier.
90. What are the types of class B amplifier?
