[Evan-Purkhiser]

Been learning electronic PCB design the last few weeks while retrofitting some IKEA window shades for Zigbee enabled motorization.

I've really enjoyed the journey of 3D printing and being able to create all kinds of mechanically useful things over the last few years, but I had always wanted to go even further and incorporate some non-trivial custom electronics.

For this project I had a space constraint for the motor controller board, so while I could have probably hacked together a working perfboard, it just wasn't going to be satisfying. So I finally took the plunge and spent 40 or so hours in KiCad learning how read IC reference documents, picking components, and of course, doing the PCB trace layout.

It's really just a 12v→5v buck circuit, all the plumbing and ancillary components for connecting a ESP32 module to a couple motor driver ICs, and some headers, but it is completely mine!

Just got 5 of my boards in the mail from JLCPCB the other day (insane turnaround, less than a week) and was very happy to find that the entire circuit worked perfectly! I did spend a fair amount of time going over the design with Claude though, so I think that paid off (the kicad files are plaintext, so it made easy work of understanding what I was doing).

Still putting together the repo here, but I'm hoping to make a little blog post out of the project too :) https://github.com/evanpurkhiser/HOPPVALS-MRF-01

[JKCalhoun]

That's cool.

I wanted to see the schematic in a README.md on GitHub. (Saves me having to d/l the KiCad files, open them.) It would be cool if you added that to the repo.

[shifto]

This is how it starts my friend. Before you know it you have a lot of projects 90% done and living in production without ever getting the last 10% before you think of something new! Currently I'm refactoring a lot of homebrew ESPhome devices to use the ESP32-H2 as it supports Thread. This allows me to remove weak IoT SSIDs while expanding my Thread network node count for better mesh.

[Evan-Purkhiser]

Ah I picked the C6 for it's Zigbee support, I've completely avoided WiFi IoT devices where I can in my apartment. I haven't explored thread at all yet though. Thread / Matter seems like it's going to be more open than zigbee, and potentially easier to develop for?

[skew-aberration]

Looks much better than a typical beginner, congrats. As someone with a bit of experience (and a degree) I'd just suggest that you avoid breaking up the ground plane so much. It's the single most important rule for PCB design. Traces on that side should only be short links to jump around a trace on the top side, where possible. It matters the most for SMPS, RF, etc.

[Evan-Purkhiser]

Appreciate the feedback! I was having a hard time finding anyone with design experience in my social circle, so I mostly relied on asking Claude if something was or wasn't conventional. I did try to keep my ground pour free of bottle-necks.

[skew-aberration]

I've seen even pros make all kinds of mistakes, since PCB layout isn't really a focus of EE education. It's interesting that you've done so well with Claude. The usual temptation of beginners is to treat layout as a spatial puzzle to minimize area, but that's like minimizing LOC by reusing one letter global variables. The goal should be to maximize the quality of the important signals. If you need to make it smaller, you just add more layers.

The basic rule is that current flows in a loop, which means on both sides of the board. Every time there is a gap in the ground plane, current has to take a different path on the top and bottom sides. The further apart these paths are, the more like an antenna/transformer winding they act - picking up and emitting high frequency noise.

The simplest strategy is to keep all traces on the top mostly horizontal. Whenever a trace needs to cross the others, you add some vias and route it vertically on the opposite side.