Circuit for automatic gain control with constant response time

摘要

A circuit for automatic gain control of a feedback system in a time that is essentially constant regardless of the signal level includes a device for producing a signal that is representative of the output of the circuit. The signal is compared with a fixed reference to determine an error signal. The error signal is multiplied by its own time integral to obtain a control signal for a weighter that is cascaded with an amplifier to provide a controlled forward path. By this means, gain of the controlled forward path is controlled within a time that is substantially independent of signal strength.