Front-end signal detector and method for improving noise immunity of a capacitive touch sensor

摘要

A front-end signal detector and a method for improving noise immunity of a capacitive touch sensor start counting a preset time to trigger an interrupt signal responsive to a positive or negative edge of a periodic noise, to break the path through which a demodulated signal comes into a low-pass filter, to prevent noise from accumulating in the low-pass filter, and consequently mitigate the influence of the noise on the detection signal generated by the front-end signal detector.