Explain the function of base region of a transistor. Why is this … - Vidyadip

Question

Explain the function of base region of a transistor. Why is this region made thin and lightly doped? Draw a circuit diagram to study the input and output characteristics of n-p-n transistor in a common emitter (CE) configuration. Show these characteristics graphically. Explain how current amplification factor of the transistor is calculated using output characteristics.

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Answer

Its acts as interface between emitter and collector. or It controls/regulates the charge carriers moving from emitter to collector. To minimise base current or ensuring that most of current carriers, moving out of the emitter, move directly from emitter to collector.

Current amplification factor: This is defined as the ratio of the change in collector current (output current) to the change in base current. $\beta = \bigg(\frac{\bigtriangleup\text{I}_{c}}{\bigtriangleup\text{I}_{B}}\bigg)_{\text{V}_{cb}}$.

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