SMPS MCQ

1. SMPS stands for

  1. single-mode power supply
  2. store mode power supply
  3. start mode power supply
  4. switched-mode power supply
Answer
Answer. d

2. SMPS is used for

  1. switch from one source to another source
  2. the storage of dc power
  3. obtaining controlled dc power supply
  4. obtaining controlled ac power supply
Answer
Answer. c

3. The device used for switching in a switched Mode Power supply is

  1. Diode
  2. Thyristor
  3. GTO
  4. MOSFET
Answer
Answer. d

4. Consider the following statements:

Switched-mode power supplies are preferred over the continuous types because they are

  1. suitable for use in both ac and dc
  2. more efficient
  3. suitable for low-power circuits
  4. suitable for high-power circuits

Which of these statements are correct?

  1. i and ii
  2. i and iii
  3. ii and iii
  4. iii and iv
Answer
Answer. c

5. What are the advantages of switching power supplies over linear power supplies?

  1. The devices operate in linear/active region.
  2. The devices operate as switches.
  3. Power losses are less.

Select the correct answer using the code given below

  1. ii and iii
  2. i and iii
  3. i, ii and iii
  4. i and ii
Answer
Answer. a

6. Which one of the following is the main advantage of SMPS over linear power supply?

  1. No transformer is required
  2. Only one stage of conversion
  3. No filter is required
  4. Low power-dissipation
Answer
Answer. d

7. 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

8. Which one of the following is used as the main switching element in a switched-mode power supply operating in 20 kHz to 100 kHz range?

  1. Thyristor
  2. MOSFET
  3. TRIAC
  4. UJT
Answer
Answer. b

9. In a switched-mode power supply (SMPS), after conversion of a.c. supply to a highly filtered d.c. voltage, a switching transistor is switched ON and OFF at a very high speed by a pulse width modulator (PWM) which generates very-high frequency square pulses. The frequency of the pulses is typically in the range of

  1. 100 Hz-200 Hz
  2. 500 Hz-1 kHz
  3. 2 kHz-5 kHz
  4. 20 kHz-50 kHz
Answer
Answer. d