Reply 100 of 240, by Sphere478
CalamityLime wrote on 2022-06-05, 19:28:
3.3 from the pico at could be handy. You'd want a nice stable connector […]
3.3 from the pico at could be handy. You'd want a nice stable connector
Some simple feedback:
Make the pads for the ATX connector larger (and the AT connector if there's space). The pads you have are on the smaller side, I think you'll find that solder will ball up on the conductor itself without a good contact to the pad. I've had issues with tiny pads doing this on even leaded solder.
I do see that you have nice thick traces for the -12 and -5 volt rails but to make room for the pads here are some numbers that might help:
You have the thick traces at around 50mil (1.25mm) which is good for around 1.4amps but most negative rails are about half an amp to an amp.
You're not going to see a whole amp on either the -12 or -5 but to accommodate an amp you want around 32mil which is about 0.8mm.
It's a signal line so you don't need much. To accommodate say half an amp (can't find a proper spec but it feels right) you want a trace about 0.35mm
I'm giving trace thickness measurements based on 1oz copper, if you're using 2oz copper than you can half the thickness.
Hope that helps a bit.
I had to find some of information on trace thickness for the USB-2-232-KBD to deal with RGB keyboards. Ultimately it came down to fitting the thickest trace I could fit.
Might play around with the pads and traces. Thx for input.
Here is a pic of a soldered unit (prev version) latest versions were (re)done by me, but original was from wiretap.
If you wanna play with it, the thread is posted above, you could post your version. It’s open source.
I’ll probably put one of these together myself soon. And report results about the pads. 😀 ( I already ordered)