Voltage storage circuit useful in television receiver control applications

摘要

A circuit for storing a DC voltage which may be used to control the volume, brightness, contrast, tint or color characteristics of a television receiver includes a semiconductor switching circuit for selectively coupling a DC voltage to a voltage storage capacitor through a DC impedance path. The DC impedance path is coupled between the inverting and noninverting inputs of an operational amplifier. The output of the operational amplifier is coupled to a utilization circuit to be controlled. A feedback path is coupled between the operational amplifier's output and inverting input to provide negative feedback so that a voltage balance is maintained between the inverting and noninverting inputs and thereby substantially eliminate leakage current flow to or from the storage capacitor through the DC impedance path.