Operational amplifier with digitally programmable gain circuitry on the same chip

摘要

A single chip operational amplifier wherein the gain is programmable by means of a digitally controlled feedback loop wherein the parameters of the feedback circuit are digitally programmable under control of a microprocessor, microcontroller, control logic and the like. There is provided an operational amplifier with a feedback loop from output terminal to input terminal. The feedback loop contains components which are switched into the feedback loop circuit under control of digital signal provided by an external device, such as, for example, a microprocessor, microcontroller, control logic and the like. The digital signals from the external device cause the appropriate resistors and/or capacitors and/or other components, as may be required, to be switched into the feedback loop of the operational amplifier to provide the desired gain. These digital signals can be derived from a monitoring source which is designed to provide automatic gain control (AGC) or the like.