Earlier this year we built the electronic badges for the Open Source Hardware Summit. The badge was very nice as is, but I extended it with a LiPoly battery pack of my own design. The badges were assembled in our shop here, so they look great (except where I modded mine). The LiPoly board, however, was hand soldered by me at home. I don’t have anywhere near the skill that our technicians do, but I still like to build stuff on my own from time to time.
The green board is mine – again, I hand soldered it, which is why it’s so messy. In addition to having the LiPoly battery management chip, it has a 3.3 volt regulator and an FT230X USB to TTL UART converter chip. It’s a pretty handy little device when I’m working on just about any microcontroller based project.
For some reason, I decided it’s time to make it smaller though – and have it professionally built. Even for me, this was far from my best work. I’m going to replace the FT230X (U2 on the right in a SO16 package) with a small QFN, similar to the part sitting next to the badge. Most of the passives will go to 0402 or 0201 and the overall size of the board will end up about half what it is now.
The actual FT230XQ part is a 16 pin 4 mm x 4 mm QFN with 0.65 mm pad pitch. Not the most challenging part, but I didn’t have a footprint or symbol for it. Rather than introduce more opportunity for error by making the symbol and footprint myself, I went to SnapEDA and found the part.
It really is as easy as a quick search, download, and copy to my libraries directory. If they don’t have the particular footprint you need, you can have them make it for you.
I have a little more work to do on the design before I run it through the shop here, and a few decisions to make. I may go to a USB Type-C connector to future proof it. The downside to doing so is that, for now, I have far more USB micro-B chargers and cables, and the FT230X won’t handle high speed signals. It might give the impression that the board supports high speed when it doesn’t. If I do go that route, I checked and SnapEDA does have the footprint I need.
Stay tuned, and in the meantime, if you need something professionally built with awesome robot pick and place machines, drop on over to www.screamingcircuits.com for an online quote.
I’d like to blame someone for my atrophied soldering skills