CAPACITANCE COMPENSATION CIRCUIT FOR DIFFERENTIAL AMPLIFIER

摘要

A differential amplifier is often used as a signal conditioner for low level transducer pick-ups. In many such applications the differential amplifier is remotely located with respect to the transducer. If there is amplifier input capacitance, or capacitance from either transmission line to any potential other than that of a driven guard, differential error signals may be derived from common mode potentials. There is here disclosed circuit means for compensating for amplifier input capacitance and/or transmission line capacitance to unguarded potentials by use of regenerative feedback of the amplified common mode signal to each input of the differential amplifier.