Emitter bias:

Figure: Emitter bias

While a split supply (dual power supply) is accessible, this biasing circuit is the very much effective, and gives zero bias voltage at the emitter or collector for load. The negative supply V_EE is employed to forward-bias the emitter junction by R_E. The positive supply V_CC is employed to reverse-bias the collector junction. Just only two resistors are essential for the common collector stage and 4 resistors for the common emitter or common base stage.

We know that,

V_B - V_E = V_be

If R_B is sufficiently small, base voltage will be almost zero. Hence emitter current is,

I_E = (V_EE - V_be)/R_E

The operating point is independent of β if R_E >> R_B/β

Merit:

Good stability of operating point identical to voltage divider bias.

Demerit:

This type can just only be used while a split (dual) power supply is available.