
584 Microwave Engineering
in CB and CE congurations. There is no current ow in the emitter termi-
nal at load when the transistor operates in the cutoff mode. In the saturation
mode, the load current approaches its maximum value. This conguration
can also be used as a switch or pulse amplier. It however differs from the
CE conguration as its voltage gain is slightly less than one but its current
gain is very high (≈
β
+ 1). This aspect makes the common collector congu-
ration useful for power amplication.
14.3.1.3 Biasing and Modes of Operation
For the proper operation of a transistor, its different junctions need to be
connected to