AUTOMATIC GAIN AND OFFSET COMPENSATION FOR AN ELECTRONIC CIRCUIT

摘要

Gain offset and voltage offset compensation for a controllable gain element of a circuit is effected in response to a gain offset value and voltage offset value. A current operating condition of the circuit is sensed and compared to a nominal operating condition. If the current operating condition is outside the nominal operating condition by more than a threshold, a calibration operation to set the gain and voltage offset values is performed. The gain offset value is selected as a function of the sensed current operating condition. With respect to the voltage offset, differential input terminals of the controllable gain element are shunted and the output is measured. The measured output value of the controllable gain element is applied as the voltage offset value. The operating conditions at issue may be one or more of supply voltage and temperature.

主权项

1. A circuit, comprising:
a controllable gain element having a differential input and an output and operable to effect gain offset and voltage offset compensation in response to a gain offset value and voltage offset value; a differential shunt circuit coupled to the differential input of the controllable gain element; a sensing circuit configured to sense a current operating condition of said circuit; and a control circuit operable responsive to said sensed current operating condition to: detect that the current operating condition of the circuit is outside a nominal operating condition; apply as said gain offset value a value selected as a function of the sensed current operating condition; actuate the differential shunt to connect terminals of the differential input to each other; sense a value at the output of the controllable gain element; and apply the sensed value as said voltage offset value.