Question

The given figure shows an npn transistor.

1. Redraw the figure and show the biasing voltage, direction of current and direction of ow of electrons and holes.

2. Draw the input and output characteristics of transistor connected in common emitter configuration.

3. In a transistor, a change of 7.9 mA is observed in the collector current for a change of 7.99 mA in the emitter current. Determine the change in base current.

Answer 1

2. Input characteristic

Output characteristic

3. ∆I_E = ∆I_c + ∆I_B, ∆I_c = 7.9 mA, ∆I_E = 7.99 mA

∆I_B = ∆I_E – ∆I_c

= 7.99 – 7.9 = 0.09 mA.