Projected Capacitive Technology

Projected Capacitive Technology (PCT) is fast becoming one of the most prevalent touch technologies for an expanding variety of applications ranging from consumer devices to commercial applications in retail, gaming and signage. Driven by the increasing number of users of touch-enabled mobile devices, consumer and professional expectations for touch applications have moved far beyond single touch requirements into the realm of multi-touch and multi-user capabilities. Since "projected capacitive technology" is a relatively broad term this document explores two of the most prominent sensing methods, "self capacitance" and "mutual capacitance", and the different options within these sensing methods. Each of these sensing methods address different needs and understanding their strengths and capabilities can help hardware and software developers choose the appropriate touch technology for their application.