FEEDBACK AMPLIFIER WITH BRIDGE-STABILIZED OUTPUT IMPEDANCE

摘要

An impedance-matching arrangement comprising an operational amplifier with a bridge-stabilized output impedance transfers power between circuits having a common ground. The resulting stable gain and impedance extend over a wide frequency range and minimize impedance-matching power losses. The output impedance of the amplifier is modified to incorporate a Wheatstone bridge, three of whose arms are resistive and the fourth is the output impedance of the amplifier. One bridge diagonal feeds the grounded load circuit and the other supplies symmetrical feedback currents to the respective inputs of the amplifier.