Power Semiconductor Diodes & Transistors MCQs

1. In a diode, the cut-in voltage and forward voltage drop are respectively

  1. 0.7 V, 0.7 V
  2. 0.7 V, 1 V
  3. 0.7 V, 0.6 V
  4. 1 V, 0.7 V

Answer
Answer. b

2. The reverse recovery current in a diode depends upon

  1. storage charge
  2. forward field current
  3. PIV
  4. temperature

Answer
Answer. b

3. A power MOSFET has three terminals called

  1. collector, emitter, and base
  2. drain, source, and gate
  3. drain, source, and base
  4. collector, emitter, and gate

Answer
Answer. b

4. As compared to power MOSFET, a BJT has

  1. Higher switching losses and higher conduction loss
  2. Lower switching losses but higher conduction loss
  3. Lower switching losses and lower conduction loss
  4. Higher switching losses but lower conduction loss

Answer
Answer. d

5. Choose the correct statement

  1. Both MOSFET and BJT are voltage controlled devices
  2. MOSFET is a voltage controlled device whereas BJT is a current controlled device
  3. Both MOSFET and BJT are current controlled devices
  4. MOSFET is a current controlled device where is BJT is a voltage controlled device

Answer
Answer. b

6. Choose the correct statement

  1. Both MOSFET and BJT has negative temperature coefficient
  2. Both MOSFET and BJT have positive temperature Coefficient
  3. MOSFET has positive temperature Coefficient where is BJT has negative temperature Coefficient
  4. MOSFET has negative temperature Coefficient where is BJT has positive temperature coefficient

Answer
Answer. c

7. An IGBT has three terminals called

  1. Drain, source, and base
  2. Collector, emitter, and base
  3. Drain, source, and Gate
  4. Collector, emitter, and Gate

Answer
Answer. d

8. The softness factor for soft recovery and fast recovery diode are respectively

  1. 1, > 1
  2. < 1, 1
  3. 1, 1
  4. 1, < 1

Answer
Answer. d

9. An MCT has three terminals called

  1. Drain, source, and gate
  2. Collector, emitter, and gate
  3. Drain, source, and base
  4. anode, cathode, and gate

Answer
Answer. d

10. Secondary breakdown occurs in

  1. MOSFET but not in BJT
  2. Both MOSFET and BJT
  3. BJT but not in MOSFET
  4. None of the above

Answer
Answer. c

11. In the conduction mechanism of Schottky diode

  1. Both holes and electrons participate
  2. Only holds can participate
  3. Only electrons can participate
  4. None of these

Answer
Answer. c

12. The semiconductor device which is suitable for induction hardening in radio frequency range is

  1. MCT
  2. MOSFET
  3. BJT
  4. IGBT

Answer
Answer. b

13. High-frequency operation of a circuit is limited by

  1. Off state loss in the device
  2. Switching losses in the device
  3. On state loss in the device
  4. All of the above

Answer
Answer. b

14. Which of the following devices should be used as a switch in a low power switched mode power supply (SMPS)?

  1. GTO
  2. MOSFET
  3. TRIAC
  4. Thyristor

Answer
Answer. b

15. When compared with BJTs, MOSFETs have lesser turn off time, enabling them to operate at high operating frequencies. What is the reason that can be attributed to that property?

  1. Smaller leakage current of MOSFETs
  2. The absence of minority storage charge in the MOSFETs
  3. High input impedance of the MOSFETs
  4. Positive temperature coefficient of the MOSFETs

Answer
Answer. b