Darlington transistor

A compound semiconductor device consisting of two transistors in which the collectors are connected together and the emitter of the first transistor is connected to the base of the second transistor.

NOTE 1 The two transistors connected in this manner may be regarded as a compound transistor with three terminals.

NOTE 2 The circuit may include a biasing network.

NOTE 3 The presence of a terminal to provide direct access to the base of the second transistor is optional.

Graphic symbols (ref. IEEE Std 315):

NOTE In the graphic symbols, the envelope is optional if no element is shown connected to the envelope.

References