Question

Draw the circuit diagram for studying the characteristics of a transistor in common emitter configuration. Explain briefly and show how input and output characteristics are drawn.

Answer 1

(i) The base of the transistor is lightly doped i.e. the number density of majority carriers in the base is always lesser as compared to emitter or collector.

(ii) The emitter supplies the majority carriers for current flow.

(ii) The collector collects the majority carriers.

n-p-n Transistor circuit diagram :

For input characteristics: At constant V_CE, for different values of V_BE, different values of I_B are obtained.

For output characteristics: At constant I_B, for different values of V_CE, different values of I_C are obtained.