Patent ID: 7373266

Claim:
A method for calibrating a sensor circuit that includes a sensor that is configured to sense a physical parameter and generate an electrical sensor output signal representing the physical parameter, a temperature measurement circuit configured to output a measured temperature, and a signal processing path coupled to the sensor so as to receive the electrical sensor output signal and use the measured temperature to compensate for temperature variations in the electrical sensor output signal, the method comprising: an act of measuring a first value of an output voltage of the signal processing path while exposing the sensor circuit to a first temperature and a first value of the physical parameter; an act of measuring a second value of the output voltage of the signal processing path while exposing the sensor circuit to approximately the first temperature and a second value of the physical parameter; an act of measuring a third value of the output voltage of the signal processing path while exposing the sensor circuit to a second temperature and approximately the first value of the physical parameter; an act of measuring a fourth value of the output voltage of the signal processing path while exposing the sensor circuit to approximately the second temperature and approximately the second value of the physical parameter; an act of disconnecting the signal processing path from using the measured temperature of the temperature measurement circuit to compensate for temperature variations in the electrical sensor output signal during the acts of measuring the first, second, third, and fourth values of the output voltage of the signal processing path; and an act of at least estimating at least one of an offset of the signal processing path, an offset temperature coefficient of the signal processing path, a gain of the signal processing path, and a gain temperature coefficient of the signal processing path at least indirectly using the measured first, second, third and fourth values of the output voltage.