Semiconductor Electronics

For a p-type semiconductor, which of the following statements is true?

1. Holes are the majority carriers and trivalent atoms are the dopants.
2. Holes are the majority carriers and pentavalent atoms are the dopants.
3. Electrons are the majority carriers and pentavalent atoms are the dopants.
4. Electrons are the majority carriers and trivalent atoms are the dopants.

In the combination of the following gates the output Y can be written in terms of inputs A and B as [figure]

1. A.B
2. A. B + A.B
3. A. B + A.B
4. A + B

In a p-n junction diode, change in temperature due to heating

1. affects only reverse resistance
2. affects only forward resistance
3. does not affect resistance of p-n junction
4. affects the overall V - I characteristics of p-n junction

In the circuit shown in the figure, the input voltage Vi is 20 V, VBE = 0 and VCE = 0. The values of IB, IC and β are given by [figure]

1. IB = 40 , IC = 10 mA, β = 250
2. IB = 25 , IC = 5 mA, β = 200
3. IB = 20 , IC = 5 mA, β = 250
4. IB = 40 , IC = 5 mA, β = 125

The given electrical network is equivalent to [figure]

1. OR gate
2. NOR gate
3. NOT gate
4. AND gate

Which one of the following represents forward bias diode ?

1. [figure]
2. [figure]
3. [figure]
4. [figure]

In a common emitter transistor amplifier the audio signal voltage across the collector is 3 V. The resistance of collector is 3 k . If current gain is 100 and the base resistance is 2 k , the voltage and power gain of the amplifier is

1. 15 and 200
2. 150 and 15000
3. 20 and 2000
4. 200 and 1000

To get output 1 for the following circuit, the correct choice for the input is [figure]

1. A = 1, B = 1, C = 0
2. A = 1, B = 0, C = 1
3. A = 0, B = 1, C = 0
4. A = 1, B = 0, C = 0

Consider the junction diode as ideal. The value of current flowing through AB is [figure]

1. 10-1 A
2. 10-3 A
3. 0 A
4. 10-2 A

A npn transistor is connected in common emitter configuration in a given amplifier. A load resistance of 800 is connected in the collector circuit and the voltage drop across it is 0.8 V. If the current amplification factor is 0.96 and the input resistance of the circuit is 192 , the voltage gain and the power gain of the amplifier will respectively be

1. 4, 4
2. 4, 3.69
3. 4, 3.84
4. 3.69, 3.84