51. The time taken by the diode to operate in the reversed condition from forward conduction.
A. Maximum power time
B. Reverse recovery time
C. Lifetime
D. Time allocation
52. Approximately, the atomic weight of germanium is
A. 32
B. 28.09
C. 72.7
D. 16
53. Atomic weight of silicon at 300 K is
A. 28.09
B. 72.7
C. 5.32
D. 16
54. An LED and phototransistor is equivalent to a/an
A. Thermocouple
B. FET
C. Optocoupler
D. Regulator
55. Optocoupler is otherwise known as
A. Laser
B. Photodiodes
C. Optoisolator
D. Photoconductive cell
56. When the emitter junction is forward biased while the collector junction is reverse biased, the transistor is at ________ region.
A. Cut-off
B. Saturation
C. Active
D. Breakdown
57. When both emitter and collector junction are forward biased, the transistor is said to be at _________ region.
A. Active
B. Cut-off
C. Breakdown
D. Saturation
58. An equivalent circuit of a diode in which it is represented as a switch in series with a barrier potential.
A. First approximation
B. Second approximation
C. Third approximation
D. Fourth approximation
59. Which of the following is the equivalent circuit for a diode for third approximation?
A. A switch only
B. A switch in series with a battery in series with a resistance
C. A switch in series with battery
D. A switch in series with a resistance
60. A silicon crystal is a/an ___________ of a semiconductor if every atom in the crystal is a silicon atom.
A. Extrinsic
B. Intrinsic
C. P-type
D. N-type
61. With pnp voltage divider bias, you must use
A. Ground
B. Negative power supplies
C. Positive power supplies
D. Resistors
62. Two pn silicon diodes are connected in series opposing. A 5 V voltage is impressed upon them. Find the voltage across each junction at room temperature when nVT= 0.052 V.
A. 0.236 V, 3.2 V
B. 4.764 V, 0.236 V
C. 0.036 V, 4.964 V
D. 3.21 V, 1.79 V
63. A half-wave signal has a period of
A. 16.7 ms
B. 8.3 ms
C. 16.7 µs
D. 8.3 µs
64. A full-wave signal has a period of
A. 16.7 µs
B. 8.3 µs
C. 8.3 ms
D. 16.7 ms
65. When doping increases, ________ of a semiconductor decreases.
A. Impurity
B. Conductivity
C. Bulk resistance
D. Minority carrier
66. Which of the following has the least noise level?
A. FET
B. BJT
C. Triode
D. Tetrode
67. Which of the following has the highest input impedance
A. FET
B. BJT
C. MOSFET
D. Crystal diode
68. The frequency of a half-wave signal is
A. Twice the line frequency
B. Equal to the line frequency
C. One-half of the line frequency
D. One-fourth the line frequency
69. For a full-wave rectifier, the output frequency
A. Equals one-half the input frequency
B. Equals the line frequency
C. Equals two times the input
D. Is three times the line frequency
70. The averaged dc voltage of a half wave rectifier circuit is _________ of the value of the peak input voltage.
A. 63.6%
B. 31.8%
C. 4.8%
D. 6.2%
71. The average dc voltage of a full wave rectifier circuit is __________ of the value of the peak input voltage.
A. 31.8%
B. 48.1%
C. 63.6%
D. 1%
72. Typical leakage current in a pn junction is in the order of
A. µA
B. mA
C. nA
D. pA
73. The resistance of a forward biased pn junction is in the order of
A. Ω
B. mΩ
C. µΩ
D. kΩ
74. The removal by electronic means of one extremity of an input waveform is called ________.
A. Filtering
B. Clamping
C. Amplifying
D. Clipping
75. Which of the choices below does not describe a clipper circuit?
A. Limiter
B. Amplitude selector
C. Slicer
D. Baseline stabilizer
76. The varactor diode is also called as
A. Voltage-variable capacitance
B. Varicap
C. Epicap
D. All of the above
77. What diode has no depletion layer
A. Varactor
B. Varistor
C. Schottky diode
D. Shockley diode
78. Varistors are used for line filtering to eliminate spikes and dips and is also called
A. Transient regulator
B. Transient limiter
C. Transient filter
D. Transient suppressor
79. Defined as random motion of holes and free electrons due to thermal agitation
A. Fission
B. Fusion
C. Diffusion
D. Ionization
80. The temperature coefficient of resistance of a semiconductor is
A. Positive
B. Negative
C. Zero
D. Infinity
81. A large signal amplifier which is biased so that collector current flow continuously during the complete electrical cycle of the signal as well as when no signal is present
A. Class A
B. Class B
C. Class AB
D. Class C
82. A large signal amplifier which is biased so that current is non zero for less than one-half cycle.
A. Class AB
B. Class C
C. Class A
D. Class B
83. A class ____ amplifier stage operates with a small forward bias of the transistor so that some collector current flows at all times
A. A
B. B
C. AB
D. C
84. What factor is shown on a data sheet that tells how much you have to reduce the power of a device?
A. Power factor
B. Derating factor
C. Reactive factor
D. Reduction factor
85. The time it takes to turn off a forward-biased diode is called the
A. Forward recovery time
B. Reverse recovery time
C. Recombination
D. Turn-off time
86. A heavily doped semiconductor has
A. High resistance
B. No effect on the semiconductor characteristics
C. More heat dissipation
D. Low resistance
87. Gallium arsenide, aluminum arsenide and gallium phosphide are classified as
A. Elementary semiconductor
B. Secondary semiconductor
C. Intrinsic material made by doping
D. Insulators
88. A lightly doped semiconductor has
A. Low resistance
B. High resistance
C. No effect on a semiconductor
D. More heat dissipated behaviors
89. The property or ability of a material to support charge flow or electron flow
A. Resistance
B. Conductance
C. Resistivity
D. Permeance
90. What is also known as photo diffusion effect?
A. Dember effect
B. Skin effect
C. Destriau effect
D. Night effect
91. An effect that occurs within the entire bulk of a semiconductor material rather than in a localized region or junction
A. Silicon effect
B. Dember effect
C. Bulk effect
D. Destriau effect
92. The creation voltage in a conductor or semiconductor by illumination of one surface
A. Dember effect
B. Skin effect
C. Destriau effect
D. Night effect
93. What device uses a material catwhisker as its anode and is classified as a hot-carrier diode?
A. PIN
B. Point-contact diode
C. Shockley diode
D. Crystal diode
94. What is the typical operating current of an LED?
A. 50 mA
B. 10 mA
C. 20 mA
D. 5 mA
95. At absolute zero temperature, a semiconductor behaves as a/an
A. Good conductor
B. Superconductor
C. Insulator
D. Variable resistor
96. Avalanche breakdown in a semiconductor takes place
A. When forward current exceeds a certain value
B. When potential barrier is reduced to zero
C. When reverse bias exceeds a certain value
D. When forward bias exceeds a certain value
97. A cold-cathode glow-discharge diode having a copper anode and a large cathode of sodium or other material.
A. Tunnel diode
B. BARITT diode
C. Anotron
D. READ diode
98. A microwave diode in which the carriers that transverse the drift region are generated by minority carrier injection from a forward-biased junction instead of being extracted from the plasma of an avalanche region.
A. IMPATT
B. TRAPAT
C. BARITT diode
D. Esaki diode
99. What electronic circuit converts AC to DC where the DC output peak value can be greater than the AC input peak value?
A. Voltage multiplier
B. Rectifier
C. Clamper
D. Clipper
100. Which of the item below does not mean a VARACTOR diode?
A. VOLTACAPS
B. VARICAPS
C. Voltage variable capacitors
D. Variable resistance diode
