Hi,
I am working on a custom PCB with a Atemga 32u4 and I don't want to waste the GPIO's I am not using. I have limited space as getting it to route is already hard. What would be the best way to add small headers\vias in case I or someone wanted to put the extra GPIO's to use? I was thinking adding vias on the board layout near the pin and connecting them with a wire.
Thanks
If you have the Sparkfun library of parts, there are headers you can call up in the M section.
Yeah but they are way too big, I have been trying to find something smaller.
If you make them too small you will not be able to connect wires up.
You can do it as a via, give the via a signal name, and play with the Drill & Diameter settings to end up with enough pad to solder to.
Do you think a drill size of .012 is too small? It is the same as the auto routers vias. It auto sets the out and inner later diam. to 0.024 when I use that drill size.
I thinking there isn't enough room, I guess I could break out only some of them and the rest could be soldered to with a small wire directly to the pin on the micro.
Edit: I think a few could have full sized headers, at least I can break out a few digital and a few analog. Better than nothing.
0.012 is really small! Try looking at that next to a surface mount pad, see if that looks big enough to solder to.
The smalles thru hole part I've seen is 1mm pitch JST connectors, those have holes that are 1.4mm diameter/ 0.8mm drill.
Lol, they are small. I am trying to get as many with regular headers and then I will see what I can do with the rest.
If you are interested it will be a addon board for a OLED display for this:
http://www.mobilewill.us/2012/12/our-first-product-usb-tester.html
Then you can use the add-on for whatever easily since it will have the bootloader on it.