Bipolar Transistor Biasing

Bipolar Transistor Biasing

Bipolar transistor amplifiers must be properly biased to operate correctly. In circuits made with individual devices (discrete circuits), biasing networks consisting of resistors are commonly employed. Much more elaborate biasing arrangements are used in integrated circuits, for example, bandgap voltage references and current mirrors.

The operating point of a device, also known as bias point, quiescent point, or Q-point, is the point on the output characteristics that shows the DC collector–emitter voltage (V_ce) and the collector current (I_c) with no input signal applied. The term is normally used in connection with devices such as transistors.