Electronic attenuation value control circuit in which switching noise is suppressed

摘要

A digital controlled volume attenuator includes a plurality of resistors connected in series between a signal input terminal and a reference potential point and a plurality of electronic switches having one ends respectively connected to the connection points among resistors and the other ends connected in common. One of signals at the respective connection points among resistors is selected by making either one of the switches conductive to control the volume. A muting circuit is provided between a signal output terminal and the common connection point of the switches to prevent the switching noise generated by the switches from being supplied to the signal output terminal.