NOISE SUPPRESSION AND/OR REDUCTION CIRCUITS AND METHODS FOR CAPACITANCE SENSING SYSTEMS

摘要

A capacitance sensing system can include a noise detector coupled to a capacitance sensing network that generates a noise detect signal in response to noise; a delay circuit coupled to generate at least two different delayed sense signals in response to outputs from the capacitance sensing network; and a switch circuit that selectively outputs one of the delayed sense signals in response to the noise detect signal. Particular embodiments can include selectively discarding discrete analog samples of a capacitance signal when noise is detected in such a sample.