STM32F103 expansion board assembly

23 Aug 2017

This is the second part of the post on the STM32 expansion board. They turned up about two weeks after ordering, which isn’t bad at all, especially as that’s around when all the other bits turned up as well.

So here’s what they look like fresh out of the packet:

STM32F103 expansion board unpopulated

They look pretty good but it didn’t take long before I spotted the first mistake. The QFP footprints aren’t usable, as the pads are to short to use without some really fiddly soldering.

What I should have done is to break them out to separate pads, which I had the space for but didn’t think I needed to. It’ll go on the list of things to change for v1.1.

Obviously the next thing to do is assembly a board and see if it works…


I'm happy with the board, it does what I wanted it to, the QFP pads are a shame but not the end of the world.

Getting probes in to the headers isn’t easy, but it is possible. It’s still quite cramped but the only other way I can think of doing it would be to move the MCU down and have the output pins on both sides.

The problem is once you do that you’ve used up half the board. Maybe it might be worth doing a 100x50mm board that just makes using the modules easier to use/probe and putting everything else either on a separate board or just on breadboards.

STM32F103 expansion board demo

This post has been taged as STM32