DIY Capacitive Touch PCBs

3 роки тому

To start off, thanks to the video sponsor: JLCPCB for sponsoring this project. JLCPCB Prototype for $2 (Any Color): jlcpcb.com/DYE
In this video we take a bit of a dive into the theory of capacitive sensing along with some details about how to design a pcb utilizing touch sensors and an arduino library to do perform the sensing in software. I show off two boards I've designed, for linear and scroll, along with some demo code to show an example of what is possible with this application. Let me know if you guys have any cool ideas for how I can delve deeper into capacitive touch sensing projects.
References I used in the making of these prototypes:
www.arduino.cc/reference/en/l...
github.com/NicoHood/HID
datasheet.datasheetarchive.co...
www.ti.com/lit/an/slaa877/sla...
www.nxp.com/files-static/trai...
www.nxp.com/docs/en/applicati...
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Special thanks to Eric Skiff for freely providing the music used in this video off his album Resistor Anthems. His music can be found at ericskiff.com/music/
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КОМЕНТАРІ: 47

@mikejones-vd3fg Рік тому

That was actually a very good diamgram that made the capacitive touch circuit click for the first time in my electronics newb brain, thank you.

@ilovehotcakes Рік тому

Awesome project! Thank you for sharing the details! It was very helpful.

@billjudge5205 2 роки тому

This was just what I was looking for, thanks for the viddy

@KJ7JHN 2 роки тому

.96 OLED tetris game next. I'd also like to see a control panel for a stove. My stove is fine for now, but I know just around the corner, I'm going to need to create a control panel for it. Or better yet, a maytag washing machine capacitive touch interface. Not neccisarily the motor control, that would be nice, but more specifically the control panel. :)

@mohammadrooeintan5684 10 місяців тому

thanks for this video

@saimum_hassan 2 роки тому

Creative!

@quinnraymond4236 9 місяців тому

Thanks!

@sjm4306 9 місяців тому

Thank you!

@Minecarthus 3 роки тому

I love your intro !

@sjm4306 3 роки тому

Thank you! I remember way back when I spent an entire night combing through footage to piece it together, good times.

@LEECHINLEONG0705 3 роки тому

Nice this video

@NikiDorian 3 роки тому

Cool to see you are designing your own boards now. Having such an interest in minidisc an mp3 players, have you considered making your own flash-based audio player? There are various nice breakout boards for DACs and amps available for prototyping, plus stm32 and esp32 both offer solid audio development frameworks, it really shouldn't be too difficult, I presume. What do you think?

@sjm4306 3 роки тому

That's definitely on my list of projects I want to tackle. I really need to get a vlsi dac and esp32 to start playing around with.

@NikiDorian 3 роки тому

@@sjm4306 Depending on what you are aiming to do, VLSI decoder might be a good option, but I hear it is relatively low quality. If you are not afraid of C, the esp32 has an excellent audio development framework. I recently got to test it with a PCM5102a from TI, and the sound is exceptional. Only problem seem so be the fussy AAC decoder, but FLAC, mp3 and Wave play flawlessly.

@sjm4306 3 роки тому

That's interesting, didn't know the esp32 could do native flac/mp3 decoding in sw but I guess it makes sense given the clock speed and number of cores. I just ordered an esp32 to play with, cant wait to get it!

@NikiDorian 3 роки тому

@@sjm4306 Awesome! My advice is to skip the arduino for the esp32, it's too limited. Also, read the docs for the esp32 IDF and ADF. This is a super capable chip, and it's very easy to miss something. Good luck and if you have any questions, drop me a line. I'm less experienced than you for sure, but I have been researching embedded audio for almost a year and I may be able to point you at the right direction!

@extrahourinthepit 3 роки тому

@@sjm4306 Well, if you really are interested in MiniDisc electronics projects, how about a custom MiniDisc drive to use NetMD directly through your computer? I mean, sure, there were a couple PCs that featured them, but if I'm not mistaken they were all MD Data (though maybe you can look into that yourself if it may interest you)

@e.e.3141 5 місяців тому

Interesting information! Thank you very much for that. What happened to the project with the touch wheel? I'm desperately looking for a solution to control a countdown via a touchwheel. Do you have an idea for this or even better a solution?

@sjm4306 5 місяців тому

It worked but I've decided the next version needs more independent segments. I've yet to design v2.0 and I'm kind of between sponsors atm so it may take awhile for me to get around to the next batch of boards. An alternative option is to just use a replacement ipod touch wheel. They are cheap, abundant and last I checked someone reverse engineered the i2c protocol and posted an open source arduino library.

@evgeniy_a7363 Рік тому

An interesting project. And how does this button react to interference ? For example, if you put turn on a fluorescent lamp next to it.

@sjm4306 Рік тому

It'd have to be pretty close to create a false trigger. You can tune the sensitivity of the detection though if it's a problem.

@anasofiaalmeida1543 2 роки тому

How about a rotating led that signals degree position, just doing its thing runing in circles but when used like an old iPod jogwheel the position of the led stops or moves acordingly to your touch. Basicaly its What you have on expensive dj controlers. And making a costa reduced one só people can aplly it in Their cheaper dj controlers like the Pioneer dd400.

@jefbolsens823 2 роки тому

I’m wondering how you added the grained / “mesh” ground plane. Anyone knows if KiCad could do a similar thing?

@sjm4306 2 роки тому

I use eagle and it's just a regular ground plane polygon pour but in the properties menu for the plane I select grid rather than solid fill. You can even adjust the line thickness/density. I dont have much kicad experience so sorry I couldn't tell you how to do it there.

@austinwhite4566 2 роки тому

I think it’s in a nightly build, but I haven’t verified

@TianaaLee Рік тому

When designing the PCB, are the connections to the IC just tracing them through rows and columns if you’re doing a diamond shape pattern? Is there anything else to take into consideration?

@sjm4306 Рік тому

I linked a few articles that describe suggested pcb layout requirements for capacitive sensors. In general though they suggest using a grid pattern ground fill plane and keeping a minimum clearance between traces that go to cap pads and of course all other digital signals (routing at 90 degrees wrt these signals will minimize crosstalk/emi). In fact it's good practice to keep any cap traces on one layer as much as possible and route everything else on the other layer.

@ShawneeUnion 2 роки тому

Wondering if you could show how to make a gamepad pcb. Not sure if this could be adapted to work with something like a SNES controller.

@sjm4306 2 роки тому

Yep this absolutely could be made into an snes controller (it would make for an interesting video but I can already guess it will be practically useless for real gameplay lol)

@ShawneeUnion 2 роки тому

@@sjm4306 oh why so? I’m guessing this is not as sensitive as the original copper/pad method. I’m trying to build/modify a snes controller to work with an arduino to run qmk and if it works think about designing a pcb that would avoid harvesting old gamepad motherboards.

@sjm4306 2 роки тому

I like any idea for recreating new parts instead of cannibalizing old ones! Using only touch sensors though would probably be too sensitive as simply accidentally resting your fingers too close to a button can trigger it (though it's possible to make the sensing less sensitive in software this would also affect intentional presses as well). The bigger problem to me is there'd be no physical feedback (no click, mush or movement at all) to let you know it correctly registered a press other than whether or not the appropriate action in the game has occurred. It's possible to get used to this with some practice but it doesn't seem like it'd be an enjoyable experience to me. I cant imagine using such a controller for precise platforming or frantic button mashers but rpgs and slow puzzle games would probably be fine.

@KSITREVS 2 роки тому

Very cool, what are your thoughts on the TTP229 ASIC?

@sjm4306 2 роки тому

I've used the single channel version in several projects and they are great for getting touch inputs working quickly and easily. Saves the trouble of worrying about calibration or tinkering with sensitivity under different conditions.

@rodneywheeler7764 6 місяців тому

Would you be able to help advise me on a project can this same board be used as a xinput device i would like to design a controller for a special needs person and i would like to make a device like this that will allow them to make up down left right and diagonals by just sliding their finger. This will allow them to play certain games since they have limitations with their left hand. Please this would really help

@sjm4306 6 місяців тому

So there is a gamepad hid arduino library by nicohood iirc but I haven't tried it myself yet. If you need a custom pcb/software I do commissioned design work, just shoot me an email at sjm4306@gmail.com

@hamam-solutions Рік тому

what IC you have used in this project. I am looking for an IC (CONTROLLER) which I can use for 7 to 8 buttons. Do you have any suggestions.

@sjm4306 Рік тому

I used the atmega32u4, it has ~20 gpio and a native usb interface which is the reason I choose it. If you only need ~8 gpio and don't need usb then you can get away with something like a attiny84 or perhaps a atmega328p.

@jstro-hobbytech 4 місяці тому

I wouldve used an smd opamp to clean the inout signal. When theyre free though why not use trial and error insteqd of opening a book hahaha. I kid. We all do this hobby for fun. Jl are my preferred board house if i dont make my own.

@interbudelblag 2 роки тому

i din't know that it is possible without complicated modules

@aerohk 2 роки тому

Is that how the iPod scroll wheel works?

@sjm4306 2 роки тому

Yep, but the pattern on a clickwheel is different to allow more precise finger position tracking.

@paulmcguire3168 Рік тому

Are you for hire. I have an idea for a project

@sjm4306 Рік тому

Absolutely so long as it's within my ability and schedule. Shoot me an email at sjm4306@gmail.com with some info about what you want to do.

@linkmasters535 3 роки тому

Or maybe something that a person has only one hand because of an accident at work and they want to play a awesome video game but they only have one hand