Introducing a resistor in the emitter of a common amplifier, stabilizes the dc operating point against variations in

In a series regulated power supply circuit, the voltage gain A_v of the ‘pass’ transistor satisfies the condition:

The emitter coupled pair of BJT’s gives a linear transfer relation between the differential output voltage and the differential input voltage V_id only. When the magnitude of V_id is less than '$$\alpha$$' times the thermal voltage, where '$$\alpha$$' is

The circuit of Fig. is an example of feedback of the following type