US Patent 7373266 Sensor calibration using selectively disconnected temperature

Calibration of a sensor circuit that includes a sensor, a temperature measurement circuit and a signal processing path. The sensor senses a physical parameter to be measured and generates an electrical sensor output signal representing the physical parameter. The temperature measurement circuit outputs a measured temperature. The signal processing path is 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. During calibration, the output voltage of the signal processing path is measured at multiple temperatures, and at multiple values of the physical parameter being measured at each temperature while the signal processing path is disconnected from using the measured temperature of the temperature measurement circuit.