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Single Sided FT232RL USB-Serial Converter (January 25, 2008)
Unsatisfied with everything else, I present the simple, single-sided, breadboardable, FT232RL based USB to TTL Serial converter.
I know you're thinking "But everyone under the sun makes an FT232 kit!", and you're right. But they all suffer from a selection of problems:
- Double sided boards with tiny vias. Not only are these a pain to solder by hand, they also require perfect precision to etch and drill at home.
- 7 million parts butted as close to each other as the pick-and-place can tolerate. I can't assemble these with tweezers.
- Signals and power brought out to a DIL style header. There's simply no effective way to plug a DIL header into a breadboard. It's a functional system for wirewrap, perfboards, and stripboards but so is a DIP style connection. It's not very helpful for custom PCBs either, since I might as well integrate the whole circuit into the board.
- You get the idea.
The answer of course is to design a simple, roomy, single sided board, with a DIP like fit.
The design is blissfully single sided, with enough room to manipulate you're fingers and tweezers. It also uses only the common and easy 0603 sized parts (with one bigger tantalum cap although an 0603 will fit). The 2pin 0.100 headers are spaced in a convenient .600 DIP width, or, you can rotate the power header 90° about either pin and you have a connector for most breadboard power rails.
Assembly is painless enough, take your PCB (etched, bought, or otherwise) and solder the big FT232 chip (with it's indent mark toward the TX/RX header). Now you get to decide how much cautious you are. If you really don't care, place a blog of solder on the pads under the USB header; this shorts the inductor's spot. Otherwise, install the caps and inductor in their places; the tantalum will need to be right-side up with it's stripe toward the power header. Install and solder the big USB connector, and everything is golden. If you like, install pin-headers in the RX/TX and power headers, or install wire, or whatever you like.
The finished part is neat and tidy, looking like a USB connector with a PCB duck bill.
If you'd like to etch your own, the postscript files are available. The top layers are pre-mirrored for toner transfer.
| Fully Assembled | Full Kit | Bare PCB |
|---|---|---|
If you don't feel like etching the board or sourcing the components, we have a simple kit in stock. Either order a kit from the above form, or choose from assembled, unassembled, or PCB only.
Eagle3D (3) FT232 (1) Kit (11) PCB (6) Serial (5) SingleSided (3) SMD (2) USB (3)
Posted by spiffed at January 25, 2008 12:27 PM