Proximity sensor and controller

Abstract

A proximity sensor includes one or more detection electrodes to be capacitively coupled to an object, a contact electrode contactable with the object, an excitation circuit connected to one of the one or more detection electrodes or the contact electrode to supply an excitation voltage to the electrode to which the excitation circuit is connected, and a detection circuit connected to the other of the one or more detection electrodes or the contact electrode to generate, based on a detection voltage at the electrode connected to the detection circuit, a detection signal in response to an electrostatic capacitance between the one of the one or more detection electrodes and the object. The detection circuit generates the detection signal in response to the electrostatic capacitance. The detection signal indicates a proximity of the object in contact with the contact electrode to the one of the one or more detection electrodes.