MCQs on

 Zener Diode MCQ

Q1. Zener diodes are also known as

a) Voltage regulators

b) Forward bias diode

c) Breakdown diode

d) None of the above.

Answer: c

Q2. In Zener diode, the Zener breakdown takes place at

a) above 6 V

b) below 6 V

c) at 6 V

d) None of the above

Answer: b

Q3. The current in a Zener diode is controlled by

a) Zener diode resistance

b) Potential barrier

c) Reverse bias voltage

d) External circuits

Answer: d

Q4. A ____________ is a heavily doped semiconductor device which is designed to operate in the reverse biased mode.

a) ideal diode

b) Tunnel diode

c) Zener diode

d) None of the above

Answer: c

Q5. How many types of breakdowns occurs for zener diode?

a) 4

b) 6

c) 1

d) 2

Answer: d

LED (Light Emitting Diode) MCQ

Q6.  The full form of LED is _________

a) Linear emitting data

b) Light emitting data

c) Light entering diode

d) Light emitting diode

Answer: d

Q7. A light emitting diode is ___________

a) Heavily doped

b) Lightly doped 

c) Photodiode

d) Voltage regulator

Answer: a

Q8. The following material used in LED to produce infrared light

a) CdS

b) GaAS

c) Si

d) Ge

Answer: b

Q9. LED emits light when it is in _______

a) Forward biased

b) Reverse biased 

c) No bias

d) Infinite biasing

Answer: a

Q10. When forward biased LED emits the light because of

a) Light generated by breaking the covalent bonds

b) Recombination of carriers

c) Light produced by collisions

d) All of the above

Answer: a

Q11.  The efficiency of an LED to generate light is directly proportional to the

a) Level of doping

b) Applied voltage

c) Temperature

d) Current injected

Answer:  d

Q12. The typical range of forward voltage of an LED is __________

a) 5-12 V

b) 1.7-3.3 V

c) 4-8.5 V

d) 6.6-10 V

Answer: b

Q13. The color of the emitted light of an LED is depends on

a) Type of semiconductor material used

b) Construction of LED

c) Wavelength

d) Both a & c options

Answer: d


PHOTODIODE MCQ

Q14. The photodiode is a P-N junction semiconductor diode which always operates in

a) Forward biased condition 

b) Reverse biased condition

c) Both conditions

d) None of the above

Answer: b

Q15. The depletion region of the photodiode is

a) Wide

b) Narrow

c) Stable

d) Improper

Answer: a

Q16. The current flowing through the photodiode in the absence of light is called as

a) Zener current

b) Photo current

c) Dark current

d) Zero current

Answer: c

Q17. Photodiode used in the detection of 

a) Invisible light

b) Visible light 

c) No light

d) Visible and invisible light

Answer: d

Q18. In photo diode, the carriers are generated in the

a) P region 

b) N region 

c) Depletion region

d) Isolation region

Answer: c

LASER Diode MCQ

Q19. LASER stands for

a) Laser activation by stimulated emission of radiation

b) Light amplification by stimulated emission of radiation

c) Light activation by stimulated emission of radiation

d) Light amplification by strong emission of radiation

Answer: c

Q20.  The Laser diode is operated in

a) Reverse biased condition

b) Forward biased condition

c) No bias

d) Both a & c

Answer: b

POINT CONTACT DIODE MCQ

Q21. In point contact diode, the junction is formed between

a) P and N type Semiconductor

b) Metal and semiconductor

c) P type and metal

d) None of the above

Answer: b

Q22. The junction capacitance of point contact diode is typically

a) 0.1pF to 1pF

b) 5pF to 50pF

c) 0.2pF to 2pF

d) 0.01pF to 0.05pF

Answer: a

Q23. Application of Point contact diode is

a) AM Detectors

b) Voltage multipliers

c) Clipper and Clampers

d) Rectifiers

Answer: a

Q24. The operating frequencies of point contact diode is

a) 10GHz and above

b) 20GHz and above

c) 50KHz and above

d) 30KHz and above

Answer: a

Q25. The cat whisker wire present in point contact diode is used for

a) Heat dissipation

b) Preventing current flow

c) Maintaining pressure between sections

d) For charge transfer between sections

Answer: c

SCHOTTKY DIODE MCQ

Q26. A Schottky diode is also knows as

a) Hot carrier diode

b) Schottky barrier diode

c) Semiconductor diode

d) Both a and b options 

Answer: d

Q27. Which of the following type of metal used in the fabrication of schottky diode

a) Platinum

b) Chromium

c) Molybdenum

d) All of the above

Answer: d

Q28. Which of the following act as an anode in schottky diode?

a) P type Semiconductor

b) N type Semiconductor

c) Metal

d) All of the above

Answer: c

Q29. Which of the following act as a cathode in schottky diode?

a) P type Semiconductor

b) N type Semiconductor

c) Metal

d) All of the above

Answer: b

Q30.  In Schottky diode, the conduction entirely is due the _________

a) Majority carriers

b) Minority carriers

c) No carriers

d) Both a and b

Answer: a

Q31. Which of the following is the advantage of Schottky diode?

a) High leakage current

b) Higher switching speed

c) Low reverse breakdown voltage

d) None of the above

Answer: b

Q32. Which of the following is the application of Schottky  diode?

a) Swiching mode power supply (SMPS)

b) Radar systems

c) AC to DC converters

d) All of the above

Answer: d

Q33. The switching time of Schottky diode is

a) 100ps

b) 200ps

c) 300ps

d) 400ps

Answer: a

Q34. The voltage drop range of schottky diode is

a) 0.15V to 0.3V

b) 0.15V to 0.45V

c) 0.15V to 0.6V

d) 0.15V to 0.8V

Answer: b

Q35. The peak inverse voltage of schottky diode is

a) 150V

b) 100V

c) 50V

d) 200V

Answer: c

 Tunnel Diode MCQ

Q36. A tunnel diode is also known as

a) Zener diode

b) PIN diode

c) Esaki diode

d) Freewheeling diode

Answer: c

Q37. A tunnel diode has _________

a) Positive resistance region

b) Negative resistance region 

c) Both a and b

d) No region

Answer: b

Q38. Tunnel diode was invented by

a) Leo Esaki

b) James Esaki

c) Leo Tunnel

d) James Watts

Answer: a

Q39. The tunnel diode is a PN diode with

a) Very high doping in P region

b) Very high doping in N region

c) Very high doping in P and N region

d) Low doping in P and N region

Answer: c

Q40. A tunnel diode is mainly used for 

a) For rectification 

b) For high speed of chopping

c) For fast switching operations

d) To control the power

Answer: b

PIN Diode MCQ

Q41. PIN diode is a type of diode having

a) Doped extrinsic semiconductor region

b) Undoped intrinsic semiconductor region

c) Doped intrinsic semiconductor region

d) None of the above

Answer: b

Q42. ___________ is a photo detector that converts optical signals into electrical signals.

a) Zener diode

b) Photo diode

c) PIN diode

d) Tunnel diode

Answer: c

Q43. A PIN diode consists of ________ semiconductor regions.

a) Three

b) Two

c) Four

d) One

Answer: a

Q44. A PIN diode is used in________

a) Microwave switch

b) Amplifiers and rectifiers

c) Photo detector

d) Both a & c

Answer: d

Q45. The resistance of the PIN diode with positive bias voltage _______

a) Decreases

b) Increases

c) Remains same

d) Data is not sufficient

Answer: a

Varactor Diode MCQ

Q46. The Varactor diode is also referred as

a) Varicap

b) Tuning didoe

c) Epicap

d) All of the above

Answer: d

Q47. A varactor diode is commonly used for

a) Voltage regulation

b) Diode detection

c) Electronic tuning

d) None of the above

Answer: c

Q48. A varactor diode usually works in

a) Forward biased condition

b) Reverse biased condition

c) No bias

d) In the breakdown region

Answer: b

Q49. The capacitance of the varactor diode varies with

a) Inversely proportional to the reverse voltage

b) Directly proportional to the reverse voltage

c) Directly proportional to the forward voltage

d) Independent of reverse voltage

Answer: a

Q50. A varactor used in FM receivers to obtain

a) Automatic gain control

b) Automatic noise control

c) Automatic volume control

d) Automatic frequency control

Answer: d

Q51. The following is not an application of Varactor Diode

a) Phase shifter

b) Frequency tuner

c) Voltage controlled oscillator

d) Parametric Amplifier

Answer: a

Q52. Which material used in manufacturing of varactor diode?

a) Silicon

b) Gallium arsenide

c) Germanium

d) Option a or b

Answer: d

GUNN Diode MCQ

Q53. The Gunn diode is also called as

a) Esaki diode

b) Varicap 

c) Active area diode

d) Bulk diode

Answer: c

Q54. The Gunn diode has

a) One P-N junction

b) No junction

c) Two junction

d) Three junction

Answer: a

Q55. A Gunn diode is most suitable for

a) Microwave rectifiers

b) Microwave oscillators

c) Microwave amplifiers

d) Microwave Mixers

Answer: b

Q56. GaAs is used in the manufacturing of Gunn diode because:

a) It is less costly

b) It is less temperature sensitive

c) It has less forbidden energy gap

d) It has low conduction band electrons

Answer: c

Q57. The electrodes of Gunn diode are made up of:

a) Molybdenum

b) Gold 

c) Copper

d) Tungsten

Answer: a

Q58. The following is the advantage of Gunn diode

a) High RF power

b) Low noise

c) Low frequency operation

d) High turn off voltage

Answer: b

Q59. The Gunn Diode used in the range of _______

a) Below 100 MHz

b) More than 100 KHz

c) Above 15 GHz

d) Below 15 MHz

Answer: b

Q60. The noise figure of Gunn diode is around

a) 12dB

b) 20dB 

c) 30dB

d)  56dB

Answer: a

These are most asked Basic Electronics mcqs with answers and most important Special purpose diodes interview and  diode Viva question.
We hope you liked this article on industrial electronics objectives and exam questions, we will keep on posting post articles on various electronics topics, so bookmark and keep visiting our Site. Thank you.