App note: Layout and physical design guidelines for capacitive sensing

Posted on Sunday, October 30th, 2011 in app notes by DP

We think DIY capacitive touch sensing buttons, and sliders are cool. Designing and shaping your capacitive panels can be a pain. Here is an app note by Microchip that covers all the basics required to get your capacitive touch sensing project started.

This app note starts with which pad shape and size is best suited for buttons. How the choice of material, and design of the covering plate impacts the sensitivity of a the design, is covered as well. In the end they give some routing guidelines to follow in designing capacitive touch sensing projects.

One thing to note, that we liked as well, is:

Also, the sensors may be separate from the PCB.
Wires leading off-board may direct the sensors to the
location where they are to be mounted and appropriately
affixed. This can allow for very flexible designs
and permits shapes which are not flat.

This entry was posted on Sunday, October 30th, 2011 at 8:00 pm and is filed under app notes. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.

5 Responses to “App note: Layout and physical design guidelines for capacitive sensing”

  1. Willemite says:

    I only wish these would work with my gloved hands…

    • Dan says:

      They do. I’ve (accidentally) made some that could sense me from a foot away, so you can make them as sensitive as you want if you can work within that sensitivity’s minimum resolution.

    • Jan Rune says:

      Buy some conductive thread and stitch a few knots through the finger you usually use…

  2. willemite says:

    oh. yes very good point I totally blanked on the use in proximity sensing. Very good point about the spatial resolution.

  3. robberknight says:

    I recommend to also read the application note by Atmel about this topic: Touch Sensors Design Guide

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