CAPACITIVE PROXIMITY DETECTION USING DELTA-SIGMA CONVERSION

摘要

Capacitive proximity detection is provided by combining a delta-sigma modulator and a capacitive voltage divider circuit to create a high resolution capacitive-to-digital converter. Period and duty cycle counters provide duty cycle ratios from the delta-sigma modulator for comparison of changes in capacitance values of a capacitive sensor (102) when an object is in proximity thereto.