1. Which of the following condition is true for cut-off mode?
Correct : A. the collector current is zero
2. Which of the following is true for the cut- off region in an npn transistor?
Correct : B. potential difference between the emitter and the base is smaller than 0.4v
3. Which of the following is true for a typical active region of an npn transistor?
Correct : C. the potential difference between the emitter and the collector is less than 0.3 v
4. Which of the following is true for the active region of an npn transistor?
Correct : C. all of the mentioned
5. Which of the following is true for a npn transistor in the saturation region?
Correct : D. the potential difference between the collector and the base is approximately 0.5v
6. The potential difference between the base and the collector Vcb in a pnp transistor in saturation region is
Correct : B. -0.5v
7. For a pnp transistor in the active region the value of Vce (potential difference between the collector and the base) is
Correct : A. less than 0.3v
8. Which of the following is true for a pnp transistor in active region?
Correct : A. cb junction is reversed bias and the eb junction is forward bias
9. Which of the following is true for a pnp transistor in saturation region?
Correct : B. cb junction is forward bias and the eb junction is forward bias
10. For the circuit shown, find the quiescent point.
Correct : C. (10v, 3ma)
11. What is the DC characteristic used to prove that the transistor is indeed biased in saturation mode?
Correct : D. ic < βib
12. The feature of an approximate model of a transistor is
Correct : A. it helps in quicker analysis
13. 005mmhos, hre=0. Find the output impedance if the lad resistance is 5kΩ.
Correct : B. 4kΩ
14. A transistor has hie =2kΩ, hoe=25µmhos and hfe=60 with an unbypassed emitter resistor Re=1kΩ. What will be the input resistance and output resistance?
Correct : D. 63kΩ and 40kΩ respectively
15. A transistor has hie =1KΩ and hfe=60 with an bypassed emitter resistor Re=1kΩ. What will be the input resistance and output resistance?
Correct : D. 63kΩ and 40kΩ respectively
16. In the given circuit, find the equivalent resistance between A and B nodes.
Correct : B. 50kΩ
17. Which of the following acts as a buffer?
Correct : A. cc amplifier
18. Which of the following is true?
Correct : B. ce amplifier has a large current gain
19. In CB configuration, the value of α=0.98A. A voltage drop of 4.9V is obtained across the resistor of 5KΩ when connected in collector circuit. Find the base current.
Correct : C. 0.02ma
20. Which of the following is the correct relationship between base and emitter current of a BJT?
Correct : D. ie = (β + 1) ib
21. For best operation of a BJT, which region must the operating point be set at?
Correct : A. active region
22. From the given circuit, using a silicon transistor, what is the value of IBQ?
Correct : B. 47.08 ua
23. From the given circuit, using a silicon BJT, what is the value of VCEQ?
Correct : C. 6.83 v
24. From the given circuit, using a silicon BJT, what is the value of VBC?
Correct : B. -6.13 v
25. From the given circuit, using silicon BJT, what is the value of the saturation collector current?
Correct : B. 5.36 ma
26. In the given circuit, what is the value of IC if the BJT is made of Silicon?
Correct : A. 2.01 ma
27. In the given circuit, using a silicon BJT, what is the value of VCE?
Correct : B. 15.52 v
28. In the given circuit, what is the value of VE when using a silicon BJT?
Correct : D. 2.28 v
29. In the given circuit using a silicon BJT, what is the value of saturation collector current?
Correct : C. 6.67 ma
30. What is Stability factor?
Correct : A. ratio of change in collector current to change in a current amplification factor
31. The base current for a BJT remains constant at 5mA, the collector current changes from 0.2mA to 0.3 mA and beta was changed from 100 to 110, then calculate the value of S.
Correct : A. 0.01m
32. For a n-p-n transistor, the collector current changed from 0.2mA to 0.22mA resulting a change of base emitter voltage from 0.8v to 0.8005V. What is the value of Stability factor?
Correct : C. 0.04
33. There are two transistors A and B having ‘S’ as 25 and 250 respectively, on comparing the value of S, we can say B is more stable than A.
Correct : B. false
34. For a fixed bias circuit having Ic = 0.3mA and In=0.0003mA, S is
Correct : C. 11
35. For a fixed bias circuit having RC=2Kohm and VCC=60V, IB=0.25mA and S=101, find Vce.
Correct : B. 10v
36. For an ideal transistor having a fixed bias configuration, what will be the value of Beta?
Correct : C. -1
37. The temperature changes do not affect the Stability.
Correct : B. false
38. Comparing fixed and collector to base bias which of the following statement is true?
Correct : B. collector to base bias is more stable
39. The compensation techniques are used to
Correct : B. increase the voltage gain
40. Compensation techniques refer to the use of
Correct : A. diodes
41. In a silicon transistor, which of the following change significantly to the change in IC?
Correct : C. vbe
42. What is the compensation element used for variation in VBE and ICO?
Correct : A. diodes
43. The expression for IC in the compensation for instability due to ICO variation
Correct : A. βi+βio+βico
44. Which of the following has a negative temperature coefficient of resistance?
Correct : C. thermistor
45. Which of the following has a negative temperature coefficient of resistance?
Correct : D. sensistor
46. Increase in collector emitter voltage from 5V to 8V causes increase in collector current from 5mA to 5.3mA. Determine the dynamic output resistance.
Correct : B. 10kΩ
47. The output resistance of CB transistor is given by
Correct : A. ∆vcb/∆ic
48. The negative sign in the formula of amplification factor indicates
Correct : A. that ie flows into transistor while ic flows out it
49. In the given situation for n-channel JFET, we get drain-to-source current is 5mA. What is the current when VGS = – 6V?
Correct : C. 0.125 a
50. 7 BIASING BJT SWITCHING CIRCUITSJFET - DC LOAD LINE AND BIAS POINT, VARIOUS BIASING METHODS OF JFET - JFET BIAS CIRCUIT DESIGN
Correct : A. rd < 6kΩ
51. Consider the circuit shown. VDS=3 V. If IDS=2mA, find VDD to bias circuit.
Correct : C. 33v
52. To bias a e-MOSFET
Correct : A. we can use either gate bias or a voltage divider bias circuit
53. Consider the following circuit. IDSS = 2mA, VDD = 30V. Find R, given that VP = – 2V.
Correct : B. 4kΩ
54. Process transconductance parameter is 40μA/V2. Find drain to source current in saturation.
Correct : C. – 0.05ma
55. Consider the following circuit. Given that VDD = 15V, VP = 2V, and IDS = 3mA, to bias the circuit properly, select the proper statement.
Correct : A. rd < 6kΩ
56. Consider the following circuit. Process transconductance parameter = 0.50 mA/V2, W/L=1, Threshold voltage = 3V, VDD = 20V. Find the operating point of circuit.
Correct : C. 12.72v, 23.61ma
57. Which of the following relation is true about gate current?
Correct : D. ig=0
58. For a fixed bias circuit the drain current was 1mA, what is the value of source current?
Correct : C. 2ma
59. For a fixed bias circuit the drain current was 1mA, VDD=12V, determine drain resistance required if VDS=10V?
Correct : C. 2kΩ
60. Which of the following equation brings the relation between gate to source voltage and drain current in Self Bias?
Correct : B. vgs=-id rs
61. For a self-bias circuit, find drain to source voltage if VDD=12V, ID=1mA, Rs=RD=1KΩ?
Correct : C. 10v
62. Find the gate voltage for voltage divider having R1=R2=1KΩ and VDD=5V?
Correct : D. 2.5v
63. Find the gate to source voltage for voltage divider having R1=R2=2KΩ and VDD=12V, ID=1mA and RS=4KΩ?
Correct : B. 2v
64. What will happen if values of Rs increase?
Correct : B. vgs decreases
65. What is the current flowing through the R1 resistor for voltage divider (R1=R2=1KΩ, VDD=10V)?
Correct : A. 5ma
66. The h-parameters analysis gives correct results for
Correct : B. small signals only
67. For what type of signals does a transistor behaves as linear device?
Correct : A. small signals only
68. How many h-parameters are there for a transistor?
Correct : C. four
69. The dimensions of hie parameters are
Correct : B. ohm
70. The hfe parameter is called in CE arrangement with output short circuited.
Correct : B. current gain
71. What happens to the h parameters of a transistor when the operating point of the transistor changes?
Correct : A. it also changes
72. If temperature changes, h parameters of a transistor
Correct : A. also change
73. In CE arrangement, the value of input impedance is approximately equal to
Correct : A. hie
74. How many h-parameters of a transistor are dimensionless?
Correct : B. two
75. The values of h-parameters of a transistor in CE arrangement are arrangement.
Correct : C. different from that in cb
76. If the load resistance of a C.E. stage increases by a factor of 2, what happens to the high frequency response?
Correct : A. the 3 db roll off occurs faster
77. During high frequency applications of a B.J.T., which of the following three stages do not get affected by Miller’s approximation?
Correct : B. c.b.
78. Ignoring early effect, if C1 is the total capacitance tied to the emitter, what is the input pole of a simple C.B. stage?
Correct : A. 1/gm * c1
79. In a simple follower stage, C2 is a parasitic capacitance arising due to the depletion region between the collector and the substrate. What is the value of C2?
Correct : A. 0
80. For a cascode stage, with input applied to the C.B. stage, the input capacitance gets multiplied by a factor of
Correct : D. 2
81. If the B.J.T. is used as a follower, which capacitor experiences Miller multiplication?
Correct : A. cπ
82. If 1/h12 = 4, for a C.E. stage- what is the value of the base to collector capacitance, after Miller multiplication, at the input side?
Correct : C. 6cµ
83. The transconductance of a B.J.T.is 5mS (gm) while a 2KΩ (Rl) load resistance is connected to the C.E. stage. Neglecting Early effect, what is the Miller multiplication factor for the input side?
Correct : B. 11
84. Which of these are incorrect about Darlington amplifier?
Correct : D. it is a current buffer
85. In a Darlington pair, the overall β=15000.β1=100. Calculate the collector current for Q2 given base current for Q1 is 20 μA.
Correct : B. 298 ma
86. What is the need for bootstrap biasing?
Correct : B. to prevent an increase in the input resistance due to the biasing network
87. Consider a Darlington amplifier. In the self bias network, the biasing resistances are 220kΩ and 400 kΩ. What can be the correct value of input resistance if hfe=50 and emitter resistance = 10kΩ.
Correct : A. 141 kΩ
88. What is a cascode amplifier?
Correct : C. a cascade of ce and cb amplifiers
89. 1, α2 = 1.5 what is the transconductance of the entire network?
Correct : D. 55 mΩ-1
90. In the given circuit, hfe = 50 and hie = 1000Ω, find overall input and output resistance.
Correct : C. ri=956 Ω, ro=2 kΩ
91. A Differential Amplifier should have collector resistor’s value (RC1 & RC2) as
Correct : A. 5kΩ, 5kΩ
92. A Differential Amplifier amplifies
Correct : D. none of the mentioned
93. If output is measured between two collectors of transistors, then the Differential amplifier with two input signal is said to be configured as
Correct : A. dual input balanced output
94. A differential amplifier is capable of amplifying
Correct : C. ac & dc input signal
95. In ideal Differential Amplifier, if same signal is given to both inputs, then output will be
Correct : D. zero
96. Find IC, given VCE=0.77v, VCC=10v, VBE=0.37v and RC=2.4kΩ in Dual Input Balanced Output differential amplifier
Correct : C. 4ma
97. Obtain the collector voltage, for collector resistor (RC) =5.6kΩ, IE=1.664mA and VCC=10v for single input unbalanced output differential amplifier
Correct : B. 0.682v
98. In a Single Input Balanced Output Differential amplifier, given VCC=15v, RE = 3.9kΩ, VCE=2.4 v and re=250Ω. Determine Voltage gain
Correct : A. 26
99. For the difference amplifier which of the following is true?
Correct : A. it responds to the difference between the two signals and rejects the signal that are common to both the signal
100. The problem with the single operational difference amplifier is its