emitter follower

An output circuit whose output load is connected in the emitter circuit of a transistor and whose input is applied between the base and the remote end of the emitter load, which may be at ground potential.

NOTE The term "emitter follower", as applied to linear circuits, usually refers to passive-pulldown or passive-pullup (bipolar) outputs; as applied to emitter-coupled logic (ECL) circuits, to open-emitter (unipolar) outputs.

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