Project Yamhill Power Distribution Board

First, in a bit of meta-commentary, I’d like to briefly bring the new Substack chat feature to your attention. Chat was already available to users of the mobile app, but now it’s also available to web users, which I suspect would be more useful to many of my readers. One of my big goals is to build up a community, so please don’t be shy about jumping in. I’ve enabled every subscriber to be able to use chat on this Substack.

For what it’s worth, the Substack mobile app is excellent too, so if you use a smartphone, please consider grabbing it!

Power Distribution Board Design

And now onto the main purpose of this post, which is to show you the first circuit and PCB designed for Project Yamhill. Please keep in mind that my design philosophy for this project is much akin to the SpaceX Starship method: move fast and get a minimum viable product, then iterate to improve. Since everything is modular, design flaws shouldn’t be as big a show-stopper as they would be in a monolithic project.

Project Yamhill Power Distribution PCB

This was a great board for me to use to get familiar with KiCad 7.0 (the last time I used it, it was in version 5!). The quality and improvements to 7.0 are wonderful; it’s really feeling like a professional product now.

I was originally planning on using a PCB size of 1 by 2 blocks (50 mm x 110 mm), but I kept the circuit fairly simple and that board size was way too much real estate, so I shrunk everything to fit on a 1 by 1 block (50 mm x 50 mm). The board is designed to take an input of ~12 VDC, with a minimum current capacity of 2 A. There are two different linear voltage regulators on-board which also give 5 VDC and 3.3 VDC rails, each with 500 mA of capacity. These will be used for the microcontroller/user interface/LO and any additional low-voltage ICs that may be needed for RF purposes. I added a simple reverse polarity and overcurrent protection circuit, as well as indicator LEDs for each power rail. Power is taken from the board via ye olde standard 0.1” headers.

Project Yamhill Power Distribution Schematic

This is all pretty bog-standard stuff, so there’s not much need for commentary, but feel free to ask in the comments or chat if you have any questions. You can examine the design files in detail at the project’s GitHub repo.

Up Next

Next in the queue are two boards that I intend to design before I send off for a PCB order: one is going to be the “breadboard” PCB mentioned in the last post and the other will be the front panel/LO PCB, which will most likely be the most complicated single board for this project. This design is going to take some time as I spec out the circuit, so there might be a bit more of a gap between updates on this project, although I still want to post some other things in the interstitial to keep things moving at this Substack. Stay tuned!