EEVblog Electronics Community Forum
Electronics => Beginners => Topic started by: redgear on July 15, 2020, 03:38:24 pm
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I am planning to use capacitative touch button with CAP1206 (http://ww1.microchip.com/downloads/en/DeviceDoc/00001567B.pdf). Like the ones used on induction stoves. But I'm cannot find a place to buy them online. Tried Mouser, RS Components and Digikey.
Thanks
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What about the TTP223? It's only single channel, but if you search for that you'll find multichannel chips - like the TTP226:
https://rees52.com/arduino-modules/1031-ttp226-8-channel-capacitive-touch-pad-sensor-sensing-detector-module-capacitive-touch-switch-na063
Might have to get the TTP* chips from lcsc.com or aliexpress.
Also, some microcontrollers have GPIO pins which can be configured as capacitive touch switches.
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What about the TTP223? It's only single channel, but if you search for that you'll find multichannel chips - like the TTP226:
https://rees52.com/arduino-modules/1031-ttp226-8-channel-capacitive-touch-pad-sensor-sensing-detector-module-capacitive-touch-switch-na063
Might have to get the TTP* chips from lcsc.com or aliexpress.
Also, some microcontrollers have GPIO pins which can be configured as capacitive touch switches.
Thanks. But I am not looking for chips, Im looking for capacitive touch buttons. Standalone ones that I can integrate in my project.
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Something like these
[attach=1]
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^^^ This.
Capacitive touch panels (just like PCBs) are made to order. And it's cheap. Just design your own panel.
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It's hard to find anything that is not custom made.
The thing is, the NRE for making custom glass panels and a PCB backing layer for electrodes is so cheap, so why bother stocking with standard parts?
The glass is cut using laser or a dicing saw, both are mold free, only a short CNC program is needed, which can be written in minutes by a CNC programmer.
The PCB is also pretty cheap to prototype, and the print on the glass could be just inkjet printed or lithographically imaged, which requires only a printed film as a mask.
Unless you go into mass production with silk screening, there's no mold or templates involved in the entire process, thus the NRE is just labor, and most of it is actually automated.
Can you abbreviate NRE? So, I just design a PCB and place a glass over it?
^^^ This.
Capacitive touch panels (just like PCBs) are made to order. And it's cheap. Just design your own panel.
Is there a special manufacturer or all PCB manufacturers can do it?
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The only one's I've seen are really just pcb traces.
Oh, and aluminum foil.
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How do I light them from underneath? Do I need some sorta ESD protection or something?
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NRE is "non-recurring engineering costs". This is the investment for design, tooling etc. before you have a product prototype in your hand. After that it's pure production cost.
It's quite low for this kind of product, perhaps a few hundred to a few thousand dollars. OTOH, as you see with PCBs, it is probably also possible to work without NRE, provided you can produce 100% workable design files to the manufacturer.
Concerning material, backlighting, color etc. you'll really have to discuss this with the manufacturer. There's no "one size fits all".