Application Note AN4312
September 2013
This application note describes the layout and mechanical design guidelines used for touch sensing applications with surface sensors.
Capacitive sensing interfaces provide many advantages compared to mechanical user interfaces. They:
- offer a modern look and feel
- are easy to clean
- are waterproof
- are robust
Capacitive sensing interfaces are more and more used in a wide range of applications. The interface is based on surface sensors that are made of small copper foils. The sensor acts as a capacitor that is alternatively charged and discharged. The capacitor value depends on the presence of the user finger as well as the sensor design. This application note introduces various sensor designs and recommendations to achieve optimum performances, keeping in mind that none of the sensor elements should interfere with each other.
This document provides simple guidelines covering three main aspects
- Printed circuit board (PCB)
- Overlay and panel materials
- All other items in the capacitive sensor environment
Download Application Note AN4312 (996 Kb)
Related datasheets:
Equivalent touch sensing capacitances