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Barrier potential in a PN junction is caused by

A) Thermally generated electrons and holes

B) Diffusion of majority carriers across the junction

C) Migration of minority carriers across the junction
)

D) Flow of drift current

. The change in barrier potential of a silicon PN junction with temperature is

A) 0.0025 volts per degree C B) 0.0250 volts per degree C
C) 0.0030 volts per degree C D) 0.0014 volts per degree C

. Consider a PN junction in which the P side is ten times more heavily dopped than N

side. The depletion region would extend
A) Equally on both N and P sides

B)
C) More towards the N side and less towards the P side
D) Cannot be predicted

More towards the P side and less towards the N side

Negative resistance characteristics is exhibited by a

A) Zener diode B) Schottky diode 0) Photo diode D) Tunnel diode
The zener breakdown voltage as temperature is increased.

A) Decreases B) Increases

C) Remains constant D) None of the above

Varactor diodes are used in
A) Tuning of an LC circuit B) Special types of amplifiers
C) Parametric amplifiers D) All of the above

In a tunnel diode, impurity concentration is of the order of
A) 1 in 108 8) 1 in 10° C) 1 in 107 D) 1 in 109

The ripple factor of power supply is a measure of
A) Its filter efficiency B) Diode rating
C) Purity of power output D) Its voltage regulation

Transformer utilization factor of a full wave rectifier is
A) 0.482 B) 0.693 0) 1.11 D) 0.821