Patent ID: 10381993

Abstract:
Single controller automatic calibrating circuits for reducing or canceling offset voltages in operational amplifiers (op-amps) in an instrumentation amplifier are disclosed. An automatic calibrating op-amp system is provided that includes an instrumentation amplifier, which includes a front-end amplifier circuit comprising at least one front-end op-amp and a final-stage amplifier circuit comprising a final-stage op-amp. The op-amp(s) can include auxiliary differential inputs for offset voltage cancellation. The automatic calibrating op-amp system also includes an automatic calibration circuit employing a single controller to generate calibration signals on a calibration output to an auxiliary differential input(s) of an op-amp(s) in the instrumentation amplifier for offset voltage cancellation. The automatic calibration circuit includes a single controller to generate calibration signals to the instrumentation amplifier to reduce or cancel offset voltage, thereby eliminating the need to provide multiple automatic calibration circuits or an automatic calibration circuit employing multiple controllers.