Continuous capacitive slider controller for a smooth surfaced cooktop

摘要

A touch responsive capacitive control for a smooth surfaced ceramic cooktop provides a continuously variable control voltage which indicates the last touched position on an elongated control surface. An A.C. potential is applied between a transmitter plate and a pair of receiver plates all of which are positioned below the surface of the cooktop. The relative area of overlap between the touching finger and the two receiver plates varies along the length of the control surface, and the resulting change in the relative currents flowing to the two receiver plates is sensed to provide a position indication used to control the cooktop.