Semiconductor Diodes and their Applications - MCQ

Q.1

The barrier potential of a Si-diode at 0°C is about

(a) 0.3 V

(b) 0.7 V

(c) 2 mV

(d) 26 mV

Ans: b

Q.2

To produce significant forward current in a Si-diode the forward voltage must exceed 

(a) 0.3 V

(b) 0.7 V

(c) 2 mV

(d) 26 mV

Ans: b

Q.3

If the reverse-bias across a p-n junction is increased, the width of the depletion region

(a) Increases

(b) Decreases

(c) Remains unchanged

(d) None of the above

Ans: a

Q.4

The width of the depletion region in a p-n junction has a typical value

(a) 0.5 µm

(b) 0.5 µmm

(c) 0.5 cm

(d) 5 cm

Ans: a

Q.5

The cutin voltage in a Si-diode has the value

(a) 0.2 V

(b) 0.6 V

(c) 2 mV

(d) 0.6 mV

Ans: b

Q.6

The cutin voltage in a Ge-diode has the value

(a) 0.2 V

(b) 0.6 V

(c) 0.2 mV

(d) 0.6 mV

Ans: a

Q.7

A Si-diode operating at room temperature has reverse saturation current of the order of

(a) mA

(b) µA

(c) nA

(d) A

Ans: c

Q.8

A Ge-diode operating at room temperature has reverse saturation current of the order of

(a) mA

(b) µA

(c) nA

(d) A

Ans: b

Q.9

The reverse saturation current in a p-n junction is due to flow of

(a) Majority Carriers

(b) Minority Carriers

(c) Both majority and minority carriers

(d) Impurity ions

Ans: b

Q.10

Depletion region is formed in a p-n junction due to 

(a) Ionization

(b) Diffusion

(c) Recombination

(d) All of these

Ans: d