APPARATUS AND METHOD FOR DETERMINING A TOUCH INPUT

摘要

A capacitive sensor for detecting a stimulus. The capacitive sensor includes an electrode and a processing unit electrically coupled to the electrode and configured to determine the presence of a stimulus based on the rate of change of the electrode capacitance. A substrate is positioned adjacent the electrode, wherein the stimulus corresponds to the placement of an object against the substrate. The processing unit is operative to determine a time rate of change based on successive measurements of the electrode capacitance. In addition, the processing unit is operative to determine the presence of a stimulus in response to the time rate of change being less than a reference value.