Question

Draw the typical input and output characteristics of an n-p-n transistor in CE configuration. Show how these characteristics can be used to determine

(a) the input resistance (r_i ), and

(b) current amplification factor (β).

Answer 1

Input and Output characteristics

Determination of

(a) Input resistance

(b) Current amplification factor

The input and output characteristics, of a n-p-n transistor, in its CE configuration, are as shown. 

The relevant values can be read from the input characteristics. Current amplification factor

The relevant values can be read from the output characteristics,corresponding to a given value of V_CE.