Mumbai University > FE > Sem 1 > Basic Electrical and Electronics Engineering

Marks: 4 M

Year: May 2015

Output characteristics

1. Cut-off region:- Both the emitter to base and collector to base junctions are reverse biased. The base current $I_B=0$ and the collector current is equal to the reverse leakage current $I_{CEO}$.

2. Active region:- The emitter to base junction is forward biased and the collector to base junction is reverse biased. The collector current $I_C$ increases slightly with increase in voltage $V_{CE}$ However the collector current is largely depend on the base current $I_B$.

3. Saturation region:- The emitter to base junction and the collector to base junction are forward biased.

$$\boxed{\text{output resistance},r_0=\dfrac{\Delta V_{CE}}{I_C}\bigg|I_B=Constant\bigg|}$$