September 2011

Doc ID 019017 Rev 1

1/18

AN3431

Application note

How to design a PresSense pressure touch button

Introduction

Traditional capacitive touch sensing solutions offer several advantages such as reduced

cost and no mechanical moving parts. The simple mechanical design of capacitive touch

sensing systems facilitates sealing water off devices while simultaneously maintaining a

very professionnal look and feel. There are however, some limitations. Such limitations can

be addressed by capacitive sensing technology but, in a different form called press to sense

technology (PresSense).

The advantages of PresSense over traditional capacitive sensing implementations are as

follows:

whereas traditional capacitive sensing devices, with sensors that may be susceptible to

water/other contaminants, must follow special design considerations.

capacitive sensing devices cannot.

small force is required for an actuation.

This application note describes how to design a PresSense touch sensing solution using

electrodes and a metal layer.

Typical applications that are best suited for the PresSense series include:

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