Semiconductor Physics and Diodes MCQs

Question 1

There are two semiconductor diode A and B. One of them is zener whereas other is avalanche. Their ratings are 6.2 V and 24 V respectively, then

Accepted Answer

A is zener, B is avalanche

Answer

A is avalanche, B is zener

Answer

both of them are zeners

Answer

none of these

Question 2

Three identical zener diodes when connected in series were found to exhibit a breakdown at 18 V. Each of them has a breakdown potential of

Accepted Answer

6 V

Answer

18 V

Answer

54 V

Answer

none of these

Question 3

Mark the incorrect statement (with reference to zener diode)

Accepted Answer

A zener diode with a breakdown voltage of 6.2 V shall get destroyed if a voltage greater than the rated value incidently appears across the diode terminals with cathode positive and anode negative

Answer

A 6.2 V zener diode shall operate from voltages equal to or more than 6.2 V

Answer

While doing an experiment with zener diode as voltage regulator, it was observed that due to certain change in input voltage, the current through the circuit increased by a factor of 10 whereas voltage across the output terminals changed by a factor of 1-2 only.

Answer

Zener diode principle is different from that avalanche diode

Question 4

The important specifications of a zener diode are

Accepted Answer

breakdown voltage, dynamic impedance and power dissipation

Answer

its breakdown voltage and power dissipation

Answer

breakdown voltage and dynamic impedance

Answer

none of these

Question 5

A tunnel diode is an ordinary P?N junction diode with

Accepted Answer

higher impurity concentration in P and N regions

Answer

higher impurity concentration in N?region

Answer

higher impurity concentration in P?region

Answer

lower impurity concertration in P and N regions

Question 6

A typical value of impurity concentration in a tunnel diode is

Accepted Answer

1 part in 103 parts

Answer

1 part in 108 parts

Answer

1 part in 106 parts

Answer

none of these

Question 7

A higher impurity concentration

Accepted Answer

decreases the depletion width of the semiconductor junction

Answer

increases the depletion width of the semiconductor junction

Answer

does not have any effect on depletion width

Answer

none of these

Question 8

Tunnel diodes are fabricated from

Accepted Answer

either germanium or gallium arsenide

Answer

germanium

Answer

silicon

Answer

gallium arsenide

Question 9

Tunnel diode characteristic differ from ordinary junction diode characteristics in the respect that former's

Accepted Answer

exhibit a negative resistance region

Answer

are liner

Answer

non-linear

Answer

none of these