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Chapter 10: Q18CQ (page 467)

It is often said that the transistor is a basic element of amplification, yet it supplies no energy of its own. Exactly what is its role in amplification?

Short Answer

Expert verified

The role of the transistor in the amplifier is to split the input current into a tiny current flowing out of the base and a huge fraction flowing out of the collector.

Step by step solution

01

A concept:

The first N-type semiconductor from the left is called the emitter. The middle P-type semiconductor is called the base and the N-type end semiconductor is called the collector. The output circuit to drive the speaker is connected between the collector and emitter ends.

02

Role in amplification:

The input introduces minute voltage changes in the emitter-base, which changes the rate proportionally the electron flow into the base from the emitter.

A small fraction of the varying current becomes the circulating input current and the remainder becomes a proportional varying current in the output circuit.

Therefore, the transistor thus amplifies the variation in the input current.

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Most popular questions from this chapter

Question: Volumes have been written on transistor biasing, but Figure 10.45 gets at the main idea. Suppose that and that the "input" produces its own voltage . The total resistance is in the input loop, which goes clockwise from the emitter through the various components to the base, then back to the emitter through the base-emitter diode. this diode is forward biased with the base at all times 0.7 V higher than the emitter. Suppose also that Vcc = 12 V and that the "out- put" is350KΩ . Now. given that for every 201 electrons entering the emitter, I passes out the base and 200 out the collector, calculate the maximum and minimum in the sinusoidally varying

(a) Current in the base emitter circuit.

(b) Power delivered by the input.

(c) Power delivered to the output.

(d) Power delivered byVce.

(e) what does most of the work.

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