LOW FREQUENCY NOISE REMOVING METHOD AND CMOS SENSOR CIRCUIT

摘要

PROBLEM TO BE SOLVED: To enhance detection accuracy by removing low frequency noise effectively even in the case of circuitry utilizing an element having a large internal noise thereby removing adverse effect of low frequency noise caused by the internal noise in a CMOS sensor circuit. SOLUTION: An intentional offset value larger than a signal sig to be detected is preset and the ratio b/a between a value (a) obtained by measuring the preset intentional offset value through a measuring means and a value (b) obtained by measuring the magnitude of the signal sig added with the intentional offset value is utilized as a noise reduction data for reducing noise in the sensor output.