Schematic to breadboard layout

Yep, you look to have moved the neo pixel in schematic and that broke the +5V connection (the end of the wire going to the neo pixel doesn’t connect to anything. As well the 6n138 is incorrect wired in breadboard. The chip needs to be rotated 180 degrees (the current one is the correct direction for an IC which is wrong in this case). To fix that I deleted all wires connecting to the 6n137 in schematic and pcb then in breadboard clicked on the 6n137 and rotated it 180 degrees. That gets the pins in the correct place for your working circuit. As well the wire in breadboard on din pin 5 was in the incorrect place. It should go to pin 3 not pin 4 (which is nc). I also moved a couple of the wires in breadboard so there weren’t two connections on one pin (which won’t work on the real breadboard) but they are cosmetic. With those corrected you should now have a working copy of the original circuit as it is on the breadboard. here (I didn’t finish pcb however). PCB looks somewhat OK as far as routing goes, but a few suggestions:

1. Board houses charge by the square inch, so a bigger board is more expensive. In this case I’d probably mount the mega on its own (to save board space) and run jumpers or perhaps fit the circuitry in to a mega shield format and put your parts in the shield (to save the cost of the space for the mega on the board). As well you want to group the components as close together as possible (with still being able to route the traces) to minimize the cost of the board. Note if you are putting the board in an enclosure, you need to be mindful of the dimensions of the enclosure and add holes to the pcb to allow it to be screwed in to the enclosure.

2. currently the pot over lays the neopixel which you probably don’t want in practice. In fact probably the neo pixels want to go to header connectors because I would guess they will be somewhere remote from the board.

3. The usual advise for pcb routing is horizontal and vertical traces with no right angle corners (bends should be at 45 degrees). This mostly mattes in RF circuits and right angle connections would work fine here.

4. As noted the neo pixels take high current so their power leads should be separate from the power leads to the rest of the circuitry and be as wide as possible (to increase their current carrying capacity. I would actually not put the power wires on the board at all but run a large gauge wires from the power supply to the ground and +5V pins on the neo pixels. In all you look to be doing pretty good .

Chewie original circuit_fixed.fzz (157.1 KB)

Peter