[question] How to design / modify a keyboard PCB

[Laser]

I'm potentially interested in creating a custom PCB for a keyboard. Let's put aside the questions about where to actually create it, costs and so on, and focus on the creation/modification part. I don't have experience with KiCAD or other similar software, but I could learn. The question is: what would be the shortest route to obtain such a custom PCB schematic? The reason I ask this is that, on one hand, I have some very low profile, common mount, linear Alps in a non-functioning keyboard, and also a Space Invader keyboard on route (hopefully) - and these switches also have 4 pins each. I suppose I could start with an existing schematic (GH60, some open sourced TKL), and then what? It would probably involve a Teensy 2.0 or a Pro Micro.

[Matt_]

I'm potentially interested in creating a custom PCB for a keyboard. Let's put aside the questions about where to actually create it, costs and so on

Anyway: for something as electrically simple as a keyboard, you can go with the usual hobbyist's prototyping fabs, iTead or SeeedStudio (OSH Park is awesome, but too expensive for large PCBs). You can usually get five PCBs for $50-100, depending on the size.

I don't have experience with KiCAD or other similar software, but I could learn.

You will. There is no other choice

The question is: what would be the shortest route to obtain such a custom PCB schematic?

If you want the quick route, try to find an open-source keyboard and check the published files. I believe the files of the Infinity keyboard (from Input Club) have been released for instance. Perhaps you can find others.

But it would probably be best to read about keyboard design (The Living PCB Design Thread on geekhack is a great place to start, worklogs for custom keyboards are usually instructive too, regarding matrix/controller choice), and learn to use KiCAD. Keyboards are not complex devices, once you understand how they work electrically you can easily make a schematic for any kind of layout, provided you know how to use your EDA software.

About that : follow tutorials, don't rush, go one step at a time and start with a small project (a four-key PCB for instance), then when you're comfortable with the software (usually after a few hours) you can move to bigger projects.

[Laser]

Thanks for the detailed answer (and Happy New Year!)

My original idea was just to load an existing, convenient open-source schematic, and try to change the pin holes sections in some as most as possible automatic way (to account for the different, 4-pin, switch type). I'm not sure that would be possible, though - in any case, indeed I have to do my "homework" first and learn more about the whole process. Thanks again

[Matt_]

Swill mentioned that he wanted to add PCB generation to his plate building tool: https://geekhack.org/index.php?topic=65 ... msg1882102

The link to kalerator seems intriguing, but it looks like it only works with Eagle (so you need the paid version to edit large PCBs).

[Laser]

Thanks, great links! Adding one to an interesting thread: https://geekhack.org/index.php?topic=76738.0

[scottc]

Oooh Laser that is awesome! The guy even posted his plate designs. What a legend!

[Matt_]

There are even detailed files for his single-sided PCB. Great find!

[Laser]

Truly beginner's luck to find it - also it uses ExpressPCB (free )