EASY
Earn 100

Draw the symbol of an N-P-N transistor.

Important Questions on Semiconductor Devices

EASY
In a common emitter amplifier circuit using an n-p-n transistor, the phase difference between the input and the output voltages will be:
MEDIUM

In the figure, given that VBB supply can vary from 0 to 5.0 V, VCC=5 V, βdc=200, RB=100 , RC=1  and VBE=1.0 V. The minimum base current and the input voltage at which the transistor will go to saturation, will be, respectively:

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HARD
A realistic graph depicting the variation of the reciprocal of input resistance in an input characteristics measurement in a common emitter transistor configuration is :
EASY

In the following circuit, the value of β is 200 and IC is 2.5 mA. Identify the correct statement:

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EASY
For a common emitter configuration, if α and β have their usual meanings, the correct relationship between α and β is:
MEDIUM

If Iε is the emitter current, IB the base current and IC the collector current of a transistor, then which of the following statements are NOT TRUE?

(i) IEIBIC

(ii) IB<<IEIC

(iii) IC<<IEIB

(iv) IE<ICIB

MEDIUM

The transfer characteristic curve of a transistor, having input and output resistance 100 Ω and 100 kΩ respectively, is shown in the figure. The voltage and power gain, are respectively:
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HARD
With the help of circuit diagram, explain the action of an n-p-n and p-n-p transistor.
HARD
With the help of a circuit diagram, explain the input and output characteristics of a common emitter n-p-n transistor configuration. State the conclusions drawn from the characteristics curves.
EASY
The ratio (R) of output resistance r0, and the input resistance ri in measurements of input and output characteristics of a transistor is typically in the range :
EASY
An npn transistor operates as a common emitter amplifier with a power gain of 106. The input circuit resistance is 100 Ω and the output load resistance is 10 kΩ. The common emitter
current gain β will be (Round off to the Nearest Integer)
MEDIUM
A common emitter amplifier circuit, built using an NPN transistor, is shown in the figure. Its dc current gain is 250RC=1  and VCC=10 V . The minimum base current for VCE to reach saturation is

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MEDIUM

An n-p-n transistor has three leads A, B and C. Connecting B and C by moist fingers, A to the positive lead of an ammeter, and C to the negative lead of the ammeter, one finds large deflection. Then, A, B and C refer respectively to :

MEDIUM
An NPN transistor is used in common emitter configuration as an amplifier with 1 kΩ load resistance. Signal voltage of 10 mV is applied across the base-emitter. This produces a 3 mA change in the collector current and 15 μA  change in the base current of the amplifier. The input resistance and voltage gain are:
EASY
For transistor action, which of the following statements is correct?
MEDIUM

The output characteristics of a transistor is shown in the figure. When VCE is 10V and IC=4.0mA, then value of βac is 

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EASY
In an npn transistor circuit, the collector current is 10 mA. If 90% of the electrons emitted reach the collector, then
MEDIUM
The correct relation between α (ratio of collector current to emitter current) and β (ratio of collector current to base current) of a transistor is :
EASY
An unknown transistor needs to be identified as a npn or pnp type. A multimeter, with +ve and -ve terminals, is used to measure resistance between different terminals of transistor. If terminal 2 is the base of the transistor then which of the following is correct for a pnp transistor?