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प्रश्न
Draw a simple circuit of a CE transistor amplifier. Explain its working ?
उत्तर
Circuit diagram of CE transistor amplifier:
Working:
If a small sinusoidal voltage is applied to the input of a CE configuration, the base current and collector current will also have sinusoidal variations. Because the collector current drives the load, a large sinusoidal voltage v0 will be observed at the output.
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संबंधित प्रश्न
Show that the voltage gain, AV, of the amplifier is given by `A_v = (beta_(ac) R_1)/r_i`where βac is the current gain, RL is the load resistance and ri is the input resistance of the transistor. What is the significance of the negative sign in the expression for the voltage gain?
Let iE, iC and iB represent the emitter current, the collector current and the base current respectively in a transistor. Then
(a) iC is slightly smaller than iE
(b) iC is slightly greater than iE
(c) iB is much smaller than iE
(d) iB is much greater than iE.
In a normal operation of a transistor,
(a) the base−emitter junction is forward-baised
(b) the base−collector junction is forward-baised
(c) the base−emitter junction is reverse-baised
(d) the base−collector junction is reverse-baised.
Draw a circuit diagram of an n-p-n transistor with its emitter-base junction forward biased and basecollector junction reverse biased. Briefly describe its working.
Explain how a transistor in its active state exhibits a low resistance at its emitter-base junction and high resistance at its base-collector junction.
Derive the expression for the voltage gain of a transistor amplifier in CE configuration in terms of the load resistance RL, current gain a βa and input resistance.
Explain why input and output voltages are in opposite phase.
Draw a circuit diagram of an n-p-n transistor with its emitter-base junction forward biased and base-collector junction reverse biased. Briefly describe its working.
Explain how a transistor in its active state exhibits a low resistance at its emitter-base junction and high resistance at its base-collector junction.
Derive the expression for the voltage gain of a transistor amplifier in CE configuration in terms of the load resistance RL, current gain βa and input resistance.
Explain why input and output voltages are in the opposite phase.
Answer the following question.
Draw the circuit arrangement for studying the output characteristics of an n-p-n transistor in CE configuration. Explain how the output characteristics is obtained.
For the transistor circuit shown in figure, evaluate VE, RB, RE given IC = 1 mA, VCE = 3 V, VBE = 0.5 V and VCC = 12 V, β = 100.
