shows the emitter feedback bias circuit. In this circuit, the voltage across resistor RE
is used to offset the changes in bdc
. If bdc
increases, the collector current increases. This increases the emitter voltage which decrease the voltage across base resistor and reduces base current. The reduced base current result in less collector current, which partially offsets the original increase in bdc
. The feedback term is used because output current ( IC
) produces a change in input current ( IB
is common in input and output circuits.
In this case, S is less compared to fixed bias circuit. Thus the stability of the Q point is better.