Source follower with gain compensation, and circuits and methods for source follower gain error compensation

摘要

Circuits and methods for compensating for an input-dependent gain error in a buffer and/or amplifier circuit, including applying a dynamic current to the input transistor. Circuits generally include a dynamic current supply coupled to a terminal of the input transistor, the dynamic current supply providing a compensating current. The compensating current can have a magnitude equal to the output impedance of the input transistor times a magnitude of the output voltage. The compensating current can be provided via a current mirror, or directly to a terminal of the input transistor. Methods generally include regulating variations in the current through the input transistor by sinking or sourcing a static current and a dynamic current at a terminal of the input transistor. The dynamic current can be regulated in response to a variation in the input signal.