If you can reliably automate that, it's still a pretty big deal.
The author's prompt is basically already a meticulous specification of the PCB, even proactively telling the LLM to avoid certain pitfalls ("GPIO19 and GPIO20 on the ESP32-S3 module are USB D- and D+ respectively. Make sure these nets are labeled correctly so that differential routing works"). If you had no prior experience building that exact thing, writing that spec would be 95% of the work.
Anyway, I don't think the experiment is wrong, but it's also not exactly vibe-PCBing!
Nowadays most mainstream LLMs support pre-bundled prompts. GitHub Copilot even made it a major feature and tools like Visual Studio Code have integrated support for prompt files.
https://docs.github.com/en/github-models/use-github-models/s...
Also, LLMs can generate prompt files too. I recommend you set aside 10 minutes of your time to vibe-code a prompt file for PCB generation, and then try to recreate the same project as OP. You'd be surprised.
> Anyway, I don't think the experiment is wrong, but it's also not exactly vibe-PCBing!
I don't agree. Vibecoding doesn't exactly mean naive approaches to implementations. It just means you enter higher level inputs to generate whatever you're creating.
Sure, but the utility of that for PCB design wasn't demonstrated in the article. This is an expert going out of his way to give the LLM a task it can't fumble (and still does, a bit).
It’s amazing that this worked at all, but to be clear this layout is actually very bad. Just look at that minimum width trace used to carry power across the entire board and into the ESP32. Using min width traces and wrapping them and min clearance to components is a classic mistake of people (or LLMs?) that have zero understanding of PCB layout techniques beyond “draw lines until everything is connected”
It would be interesting to see if you could feed the file into an LLM and get it to produce the feedback.
Good question. KiCAD once had a router, built in, or sort of built in, but it was taken out for licensing reasons. So who's doing that?
So what did this project use?
I assumed the author was more experienced, I suppose this is more of an entry level hobbyist blog. There are some very fundamental problems with routing PCBs like this that are covered in introductory materials.
I’m puzzled why the post calls it “surprisingly good” when it’s so bad and missing basic requirements for different parts. I guess it’s surprising that anything at all was produced, but it’s weird that the author can’t identify the basic problems with the design.
This is similar to situations where someone uses an LLM to vibe code an app until it kind of works, but then an experienced developer takes one look at the codebase and can immediately see it was not developed with any understanding of the code.
Maybe _then_ we can trust LLMs to design stuff for us.
Except that:
- no parts placement
- no routing
leakycap•1h ago
Having well-established, unambiguous rules that must be followed for functionality seems to be a key predictor of AI success. The more constrained and rule bound the domain, the better LLMs perform.