Capacitive touch sensor footprint

Layout Footprints
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I hereby certify that I am not simply asking someone else to design a footprint for me.

This is an auto-generated message that is in place on the “footprints” section of the KiCad.info forum. If I remove it and ask for a footprint to be designed anyway, I understand that I will be subject to forum members telling me to go design my own footprint or referring me to a 3rd party footprint site.

Can anyone please tell me where to find a footprint for capacitive touch buttons? I couldn’t find any but I found this guide: https://ww1.microchip.com/downloads/aemDocuments/documents/TXFG/ApplicationNotes/ApplicationNotes/Capacitive-Touch-Sensor-Design-Guide-DS00002934-B.pdf

Do I need to design the simple standard button shape or do the common X-Y shape? I want to use this with the AT42QT2120 touch sensor: https://componentsearchengine.com/Datasheets/1/AT42QT2120-SU.pdf
Thanks!

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Just make it. It’s not hard and not much work.

1 Like
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KiCad has built in Wizards for these. You can enter a few parameters and then KiCad generates a custom footprint for you and loads it in the footprint editor for further modification and saving to a library.

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Didn’t know this feature existed. What’s it called?

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Yeah by the way, do those circular ones with grids work or should I use the Z-Y pattern?

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I call it “Read the Manual”.
(Also: “Wizard” is mentioned 6 times in the user manual for the PCB / Footprint editor.)

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Wow, to be honest, I didn’t know there were templates like this already

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read the datasheet and app notes carefully. there can be limits on the size/capacitance/distance that those work at. get their demo board schematics/layout and go from there. size and layout/gnd plane will depend on mechanical factors like what’s the cover material and thickness, how fast you want it to respond, and false positive rejection.