Switch device with operating modes of capacitive proximity and mechanical actuation

摘要

A switch device with two modes of operation includes at least one switch comprising, carried by a substrate, two conductive lands and an electrically conductive elastic capsule in contact with one land and, in the unoperated condition, overlying the other land so as to be capable of being urged into contact with the latter. An electrical signal from a source is applied to the capsule. A circuit measures variations of the signal due to the proximity of an electrically conductive object. The device can be used to implement matrix keyboards combining the functions of a conventional keypad and a tactile pad.