Electronic Devices & Circuits Test Questions Set 2

1)   What should be the value of stability factor in voltage divider circuit, if the ratio RB / RE tends to infinity?

a. Unity
b. Zero
c. 1 - βdc
d. 1 + βdc
Answer  Explanation  Related Ques

ANSWER: 1 + βdc

Explanation:
No explanation is available for this question!


2)   What is /are the purpose/s of adopting stabilization and compensation techniques?

a. To provide maximum bias
b. To provide thermal stabilization
c. Both a and b
d. None of the above
Answer  Explanation  Related Ques

ANSWER: Both a and b

Explanation:
No explanation is available for this question!


3)   What are the consequences of diode compensation for the change in base-to-emitter voltage (VBE) due to temperature?

a. Temperature compensation takes place by variation in forward voltage (VF)
b. Collector current become insensitive to the change in base-to-emitter voltage (VBE)
c. Both a and b
d. None of the above
Answer  Explanation  Related Ques

ANSWER: Both a and b

Explanation:
No explanation is available for this question!


4)   Generally, the resistance of thermistor decreases _______

a. Linearly with an increase in temperature
b. Linearly with the decrease in temperature
c. Exponentially with an increase in temperature
d. Exponentially with the decrease in temperature
Answer  Explanation  Related Ques

ANSWER: Exponentially with an increase in temperature

Explanation:
No explanation is available for this question!


5)   Which type of amplifiers exhibit the current gain approximately equal to unity without any current amplification?

a. CE
b. CB
c. CC
d. None of the above
Answer  Explanation  Related Ques

ANSWER: CB

Explanation:
No explanation is available for this question!


6)   What should be the level of input resistance to allow the occurrence of source loading in common base amplifier configuration?

a. Low
b. High
c. Moderate
d. Stable
Answer  Explanation  Related Ques

ANSWER: Low

Explanation:
No explanation is available for this question!


7)   The parameter 'h12' is basically a ratio of input voltage to the output voltage with the input current equal to _______

a. Unity
b. Zero
c. Infinity
d. None of the above
Answer  Explanation  Related Ques

ANSWER: Zero

Explanation:
No explanation is available for this question!


8)   The value of dBm in power measurement is estimated by assuming the reference ,which is equal to ________

a. 1mW
b. 10mW
c. 1/10 mW
d. 1/100 mW
Answer  Explanation  Related Ques

ANSWER: 1mW

Explanation:
No explanation is available for this question!


9)   Fidelity is nothing but an ability of amplifier to reproduce ________

a. Input signal without any distortion
b. Output signal without any distortion
c. Phase shift signal
d. Amplitude shift signal
Answer  Explanation  Related Ques

ANSWER: Input signal without any distortion

Explanation:
No explanation is available for this question!


10)   The rate of -20 dB/decade is almost equivalent to __________

a. -4 dB/octave
b. -6 dB/octave
c. -8 dB/octave
d. -10 dB/octave
Answer  Explanation  Related Ques

ANSWER: -6 dB/octave

Explanation:
No explanation is available for this question!


11)   Which among the below specified parameters exhibit inverse relationship with an input conductance of hybrid π model?

a. Temperature at constant hfe
b. Current at constant hfe
c. Voltage at constant hre
d. Resistivity at constant hre
Answer  Explanation  Related Ques

ANSWER: Temperature at constant hfe

Explanation:
No explanation is available for this question!


12)   The cut-off frequency (fβ) is basically the frequency at which the short circuit __________

a. CB gain of transistor drops by 3 dB from its value at low frequency
b. CE gain of transistor drops by 3 dB from its value at low frequency
c. CC gain of transistor drops by 3 dB from its value at low frequency
d. None of the above
Answer  Explanation  Related Ques

ANSWER: CE gain of transistor drops by 3 dB from its value at low frequency

Explanation:
No explanation is available for this question!


13)   Which among the following represents the frequency at which short circuit CE current gain acquires unit magnitude?

a. fα
b. fβ
c. fT
d. None of the above
Answer  Explanation  Related Ques

ANSWER: fT

Explanation:
No explanation is available for this question!


14)   Which among the following will possess a higher bandwidth, if two transistors are provided with unity gain frequency?

a. Transistor with lower hfe
b. Transistor with higher hfe
c. Transistor with lower hre
d. Transistor with higher hre
Answer  Explanation  Related Ques

ANSWER: Transistor with lower hfe

Explanation:
No explanation is available for this question!


15)   Which among the following is an output provided by transresistance amplifier?

a. Output current proportional to signal voltage
b. Output voltage proportional to signal current
c. Output voltage proportional to input voltage
d. Output current proportional to signal current
Answer  Explanation  Related Ques

ANSWER: Output voltage proportional to signal current

Explanation:
No explanation is available for this question!


16)   What would be the computational value of feedback voltage in a negative feedback amplifier with A = 100, β = 0.03 and input signal voltage = 30 mV?

a. 0.03 V
b. 0.06 V
c. 0.09 V
d. 0.15 V
Answer  Explanation  Related Ques

ANSWER: 0.09 V

Explanation:
No explanation is available for this question!


17)   After passing through which circuit/network ,does the signal Xd (output signal obtained by taking the difference of two input signals) get multiplied by '-1'?

a. Amplifier circuit
b. Feedback network
c. Mixing network
d. Sampling network
Answer  Explanation  Related Ques

ANSWER: Mixing network

Explanation:
No explanation is available for this question!


18)   Which among the below mentioned oscillators does not adopt any kind of feedback mechanism?

a. Phase-shift oscillator
b. Wein bridge oscillator
c. UJT relaxation oscillator
d. All of the above
Answer  Explanation  Related Ques

ANSWER: UJT relaxation oscillator

Explanation:
No explanation is available for this question!


19)   What is an angle of phase shift for each designed RC network in the Phase Shift Oscillator circuit?

a. 30°
b. 60°
c. 90°
d. 180°
Answer  Explanation  Related Ques

ANSWER: 60°

Explanation:
No explanation is available for this question!


20)   Which is the necessary condition of gain while designing RC phase shift oscillator in order to ensure the sustained oscillations?

a. A ≥ 29
b. A ≤ 29
c. A ≠ 29
d. None of the above
Answer  Explanation  Related Ques

ANSWER: A ≥ 29

Explanation:
No explanation is available for this question!


21)   Which among the following components is /are not involved in the feedback network configuration of LC oscillators?

a. Inductor
b. Capacitor
c. Resistor
d. All of the above
Answer  Explanation  Related Ques

ANSWER: Resistor

Explanation:
No explanation is available for this question!


22)   On which factor does the current gain (β) of power transistor depend?

a. Thickness of emitter
b. Thickness of base
c. Thickness of collector
d. All of the above
Answer  Explanation  Related Ques

ANSWER: Thickness of base

Explanation:
No explanation is available for this question!


23)   What does an arrow indicate in the below drawn schematic of V-I characteristics of n-p-n power transistor?

V-I characteristics of n-p-n Power Transistor.png
a. Primary breakdown
b. Second breakdown
c. Quasi saturation
d. Active region
Answer  Explanation  Related Ques

ANSWER: Quasi saturation

Explanation:
No explanation is available for this question!


24)   The breakdown voltage VCEV or VCEX in power transistor is the maximum voltage between collector and emitter with _________

a. Open circuited collector
b. Open circuited base
c. Base to emitter voltage that is adjusted to a specific negative value
d. Base to emitter voltage that is adjusted to a specific positive value
Answer  Explanation  Related Ques

ANSWER: Base to emitter voltage that is adjusted to a specific negative value

Explanation:
No explanation is available for this question!


25)   Which type of breakdown effect gets enhanced due to parasitic BJT action along with increase in drain current solely by the reduction in size of MOSFET?

a. Near-avalanche breakdown
b. Snapback breakdown
c. Both a and b
d. None of the above
Answer  Explanation  Related Ques

ANSWER: Both a and b

Explanation:
No explanation is available for this question!


26)   Which among the below stated transistors operate in an active region for the purpose of amplification?

a. BJT
b. E-MOSFET
c. Both a and b
d. None of the above
Answer  Explanation  Related Ques

ANSWER: BJT

Explanation:
No explanation is available for this question!


27)   Under which category/region of the below specified regions does EMOSFET operate for switching-based applications?

a. Saturation & Cut-off
b. Active & Ohmic
c. Only Saturation
d. Ohmic & Cut-off
Answer  Explanation  Related Ques

ANSWER: Ohmic & Cut-off

Explanation:
No explanation is available for this question!


28)   What does an arrow indicate in the below drawn graph of small signal operation executed by MOSFET?

Small Signal operation of MOSFET.png
a. Active Region
b. Cut-off Region
c. Saturation Region
d. Breakdown Region
Answer  Explanation  Related Ques

ANSWER: Saturation Region

Explanation:
No explanation is available for this question!


29)   What should be the value of transconductance, if N-channel E-MOSFET is biased in saturation region with the conduction parameter (k) = 0.836 mA/ V2 and drain current (ID) = 1.5 mA?

a. 1 mA/V
b. 1.5 mA/V
c. 2.23 mA/V
d. 4.23 mA/V
Answer  Explanation  Related Ques

ANSWER: 2.23 mA/V

Explanation:
No explanation is available for this question!


30)   Which among the below mentioned implementation strategies is/are precise to obtain an AC equivalent circuit of MOSFET?

A. Replacement of all capacitors by open circuits
B. Replacement of all capacitors by short circuits
C. Setting of all DC voltages to zero
D. Setting of all DC voltages to unity


a. A & C
b. B & C
c. B & D
d. A & D
Answer  Explanation  Related Ques

ANSWER: B & C

Explanation:
No explanation is available for this question!