Touch sensor design

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HeliconEnt
 
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Touch sensor design

Post by HeliconEnt »

Greetings all,

I am working on an LED lighting project using a Trinket M0 to control an ISSI LED driver IC. The LEDs will be on a board that is covered by a layer of diffusing plastic. What I'd like to do is be able to touch the cover plastic and toggle through LED sequences (rather than a button or sensor off to the side). TDK makes a conductive clear film that I thought could be used as a touch sensor. I was just curious if anyone had any experience in this type of thing or if anyone knows of a better way, because I'm a little outside my comfort zone on this one. Thanks!

Muscle Nerd Jerry

https://www.digikey.com/en/products/det ... -4/9634768

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mikeysklar
 
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Re: Touch sensor design

Post by mikeysklar »

That conductive plastic sounds like an interesting solution. Did you only want a single touch sensor input?

I normally use copper foil tape on acrylic for touch sensors inputs. You can make cool patterns and have many touch input controls.

https://www.adafruit.com/?q=copper+foil ... =BestMatch

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HeliconEnt
 
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Re: Touch sensor design

Post by HeliconEnt »

Sadly I can't use anything opaque, so copper is out. And yes, just a single input to toggle the LED sequences.

Jerry
mikeysklar wrote:That conductive plastic sounds like an interesting solution. Did you only want a single touch sensor input?

I normally use copper foil tape on acrylic for touch sensors inputs. You can make cool patterns and have many touch input controls.

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mikeysklar
 
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Re: Touch sensor design

Post by mikeysklar »

"clear conductors" really are a fascinating topic. I see a lot of research discussion comes up on that topic and very little in obtainable form today.

Maybe touch sensor isn't the best option here. Could you mount the screen with a normal pushbutton behind so when pressure is applied it activates?

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adafruit2
 
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Re: Touch sensor design

Post by adafruit2 »

you can use ITO for resistive/capacitive touch sensing
https://www.adafruit.com/product/1309

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HeliconEnt
 
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Re: Touch sensor design

Post by HeliconEnt »

adafruit2 wrote:you can use ITO for resistive/capacitive touch sensing
https://www.adafruit.com/product/1309
Marvelous, this is exactly what I need!! Thanks so much!

Muscle Nerd Jerry

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HeliconEnt
 
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Re: Touch sensor design

Post by HeliconEnt »

adafruit2 wrote:you can use ITO for resistive/capacitive touch sensing
https://www.adafruit.com/product/1309
One last question:
Software aside, is it as simple as a single lead between ITO and pin #3? I head of someone else using an additional resistor to reduce accidental triggers from static. But that was on the Tiny85 version of the Trinket.

Muscle Nerd Jerry

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Re: Touch sensor design

Post by adafruit2 »

treat it the same as any conductor - you'll need to experiement with your setup to figure out any resistors or wiring kit - it really differs each tme

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