Editing Differential amplifier (section)

==== Single-ended input ====

The differential pair can be used as an amplifier with a single-ended input if one of the inputs is grounded or fixed to a reference voltage (usually, the other collector is used as a single-ended output) This arrangement can be thought of as cascaded common-collector and common-base stages or as a buffered common-base stage.<ref group="nb">More generally, this arrangement can be considered as two interacting voltage followers with negative feedback: the output part of the differential pair acts as a voltage follower with constant input voltage (a voltage stabilizer) producing constant output voltage; the input part acts as a voltage follower with varying input voltage trying to change the steady output voltage of the stabilizer. The stabilizer reacts to this intervention by changing its output quantity (current, respectively voltage) that serves as a circuit output.</ref>

The emitter-coupled amplifier is compensated for temperature drifts, V<sub>BE</sub> is cancelled, and the [[Miller effect]] and transistor saturation are avoided. That is why it is used to form emitter-coupled amplifiers (avoiding Miller effect), [[phase splitter]] circuits (obtaining two inverse voltages), ECL gates and switches (avoiding transistor saturation), etc.