User-Accessable USB pins on USB to Serial Adapter

Around my lab we eat up USB to Serial adapters like candy. I embed one in just about every microcontroller board I make, either as part of the core functionality, or just as an easy diagnostic and bootloading tool.

Sometimes exposing the mini-B connector is the way to go, but I keep finding myself wanting to permanently attach a short length of cable ending in a USB-A connector. To do this I’ve been removing the mini-B socket and soldering wires to the pin pads, but this is cumbersome and the results can be a little flimsy (hot-glue strain relief to the rescue!). On the older adapters I used to be able to solder some of the wires to plated through-holes in the boards, but on the newer boards with the pins labeled (nice!) the through-holes are covered in soldermask or something and hard to connect to.

So, I would be really interested in a USB to Serial adapter with the four USB lines brought out to user-accessible pins. A second pair of GND and VBUS pins isn’t absolutely necessary, but it would be nice. It could just be the next iteration of the USB to Serial adapter board, maybe offered with or without the mini-B connector installed. Or even just one version with the connector, I’ve gotten pretty good at removing those guys when I don’t have space for them.


So basically you want some way to move the USB mini-B connector away from the USB-to-serial adapter to make it more accessible.

You could fashion a crude extension cable by buying this USB mini-B breakout board from Sparkfun:

Then buy a USB A to mini-B cable, plug one end in to the USB-to-serial adapter, cut it, and solder the four wires on the other end in to Sparkfun’s breakout board.


Hah! That would be something.

Actually the first time I did this was because there wasn’t physically room for the Mini-B connector on the adapter where I wanted to squeeze the board, so removing it was the only way to go.