Patent ID: 8109126

Claim:
A selective calibrating sensor circuit comprising: an electronic sensor configured to provide a sensor reading based on a characteristic of substances in proximity to the electronic sensor; a self-calibrating sensing circuit configured to receive the sensor reading from the electronic sensor and to generate a water detection signal to indicate whether the electronic sensor is immersed in water based on the sensor reading, wherein the self-calibrating sensing circuit adjusts one or more internal parameters during calibration to null an effect on the sensor reading due to contaminants or non-water substance in contact with the electronic sensor; and a sensor controller configured to receive the water detection signal, to generate a control output signal based on the water detection signal, to prohibit calibration by the self-calibrating sensing circuit when the water detection signal indicates that the electronic sensor is immersed in water, and to selectively enable calibration by the self-calibrating sensing circuit when the water detection signal does not indicate that the electronic sensor is immersed in water.