Large Signal Low Frequency Amplifiers - Electronic Engineering (MCQ) questions & answers

1)   What is/ are the necessity /ies of using a vertical structure in Power BJTs?

a. Increase in cross-sectional area to allow the flow of device current
b. Reduction in on-state power dissipation of transistor
c. Reduction in thermal resistance to keep the problem of power dissipation under control
d. All of the above
Answer  Explanation 

ANSWER: All of the above

Explanation:
No explanation is available for this question!


2)   The n_region in a vertical cross-section of a typical n-p-n bipolar power transistor is also known as _________

a. Emitter drift region
b. Base drift region
c. Collector drift region
d. None of the above
Answer  Explanation 

ANSWER: Collector drift region

Explanation:
No explanation is available for this question!


3)   Which is/are the major drawback/s of including an additional  n__drift layer in a typical n-p-n bipolar power transistor?

a. Increase in on-state device resistance by increasing on-state power loss
b. Increase in on-state device resistance by decreasing on-state power loss
c. Increase in on-state device resistance by completely stabilizing the level of on-state power loss
d. All of the above
Answer  Explanation 

ANSWER: Increase in on-state device resistance by increasing on-state power loss

Explanation:
No explanation is available for this question!


4)   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 

ANSWER: Thickness of base

Explanation:
No explanation is available for this question!


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

a. Primary breakdown
b. Second breakdown
c. Quasi saturation
d. Active region
Answer  Explanation 

ANSWER: Quasi saturation

Explanation:
No explanation is available for this question!


6)   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 

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

Explanation:
No explanation is available for this question!


7)   Which among the below stated parameters gets affected due to drift region in the power transistor?

a. Breakdown voltage
b. On-state losses
c. Switching time
d. All of the above
Answer  Explanation 

ANSWER: All of the above

Explanation:
No explanation is available for this question!


8)   Which types of power transistors have the capability to withstand the higher junction temperatures?

a. Silicon power transistors
b. Germanium power transistors
c. Both a and b
d. None of the above
Answer  Explanation 

ANSWER: Silicon power transistors

Explanation:
No explanation is available for this question!


9)   Which among the below mentioned reasons is/are responsible for the occurrence of second breakdown phenomenon in power BJT?

a. Large current
b. Distribution of current in a non-uniform manner
c. Excessive power dissipation
d. All of the above
Answer  Explanation 

ANSWER: All of the above

Explanation:
No explanation is available for this question!


10)   What is the significance of adopting an interdigitated structure of power transistors?

a. Prevention of current crowding
b. Maintenance of reasonable current densities
c. Both a and b
d. None of the above
Answer  Explanation 

ANSWER: Both a and b

Explanation:
No explanation is available for this question!