Electronic Devices And Circuits MCQ Questions & Answers

81

The dynamic resistance of diode is

A) the resistance of diode when forward biased B) the resistance of diode when reverse biased C) the AC opposition to the current flow D) none of these

Discuss

Answer & Solution

Answer: Option C

No explanation is given for this question. Let's Discuss on Board

82

A crystal diode is used as . . . . . . . .

A) an amplifier B) a rectifier C) an oscillator D) a voltage regulator

Discuss

Answer & Solution

Answer: Option B

No explanation is given for this question. Let's Discuss on Board

83

The position of the intrinsic Fermi level of an undoped semiconductor (E_Fi) is given by:

A) $$\frac{{{{\text{E}}_{\text{C}}} - {{\text{E}}_{\text{V}}}}}{2} + \frac{{{\text{kT}}}}{2}\ln \frac{{{{\text{N}}_{\text{V}}}}}{{{{\text{N}}_{\text{C}}}}}$$ B) $$\frac{{{{\text{E}}_{\text{C}}} + {{\text{E}}_{\text{V}}}}}{2} - \frac{{{\text{kT}}}}{2}\ln \frac{{{{\text{N}}_{\text{V}}}}}{{{{\text{N}}_{\text{C}}}}}$$ C) $$\frac{{{{\text{E}}_{\text{C}}} + {{\text{E}}_{\text{V}}}}}{2} + \frac{{{\text{kT}}}}{2}\ln \frac{{{{\text{N}}_{\text{V}}}}}{{{{\text{N}}_{\text{C}}}}}$$ D) $$\frac{{{{\text{E}}_{\text{C}}} - {{\text{E}}_{\text{V}}}}}{2} - \frac{{{\text{kT}}}}{2}\ln \frac{{{{\text{N}}_{\text{V}}}}}{{{{\text{N}}_{\text{C}}}}}$$

Discuss

Answer & Solution

Answer: Option C

No explanation is given for this question. Let's Discuss on Board

84

The output V-I characteristics of an enhancement type MOSFET has

A) only an ohmic region B) only a saturation region C) an ohmic region at low voltage value followed by a saturation region at higher voltages D) an ohmic region at larger voltage values preceded by a saturation region at lower voltages

Discuss

Answer & Solution

Answer: Option C

No explanation is given for this question. Let's Discuss on Board

85

When a positive d.c. voltage is applied to the n-side relative to p-side, a diode is said to be given a

A) forward bias B) reverse bias C) zero bias D) neutral bias

Discuss

Answer & Solution

Answer: Option B

No explanation is given for this question. Let's Discuss on Board

86

Let β be the short circuit common emitter current gain of a BJT biased in normal active mode. Let I_C be the collector current is this β

A) a monotonically increasing function of I_C B) a monotonically decreasing function of I_C C) initially an increasing function of I_C which reaches a plateau, and then decreases with increasing I_C D) Independent of I_C

Discuss

Answer & Solution

Answer: Option C

No explanation is given for this question. Let's Discuss on Board

87

Pinch-off voltage for a FET is the drain voltage at which

A) Significance drain current starts flowing B) Drain current becomes zero C) All free charges get removed from the channel D) Avalanche breakdown takes place

Discuss

Answer & Solution

Answer: Option C

No explanation is given for this question. Let's Discuss on Board

88

How does the dynamic resistance of diode vary with temperature?

A) Directly proportional B) Inversely proportional C) Independent D) Directly to the square of temperature

Discuss

Answer & Solution

Answer: Option A

No explanation is given for this question. Let's Discuss on Board

89

One easy way of creating biased diode clipping circuits without the need for an additional EMF supply is to use . . . . . . . .

A) Zener diodes B) PIN diodes C) Tunnel diodes D) Varactor diodes

Discuss

Answer & Solution

Answer: Option A

No explanation is given for this question. Let's Discuss on Board

90

For the n-type semiconductor with n = N_D and $${\text{p}} = \frac{{{\text{n}}_{\text{i}}^2}}{{{{\text{N}}_{\text{D}}}}},$$ the hole concentration will fall below the intrinsic value because some of the holes

A) drop back to acceptor impurity states B) drop to donor impurity states C) virtually leave the crystal D) recombine with the electrons

Discuss

Answer & Solution

Answer: Option D

No explanation is given for this question. Let's Discuss on Board

Electronic Devices And Circuits MCQ Questions & Answers | ECE