SD Adapter

I wanted to add SD Card reading to a microcontroller synthesizer project, and for that, I decided a small adapter with .1" pins for use with a breadboard would be handy.

I probably should've just gone and bought a micro-SD adapter and soldered some pins onto it, but I happened to have a dead digital camera around with an SD Card socket in it, so I took the camera apart and desoldered the surface-mount socket. I got a small piece of single-sided copper-clad board and dremeled out a very simple layout that brought the signals I needed to the edge of the board spaced at .1" intervals.

I don't have much experience with surface mount, but thanks to these excellent construction tips it was a breeze. The idea is to clean the board, flux it, pre-solder the pads, then pick up all but a little solder with some copper braid. For the final pin soldering, I used a much finer tip soldering iron than the 35w bludgeon shown here.

The board includes six 22K pull-up resistors for the card's pins. I hid five of them under the socket.

Ready for some breadboard prototyping...

Then it was time for a stereo audio output adapter. Pins 10 and 11 from a Propeller microcontroller pass through a 10K resistor and a 1uF capacitor, + toward the uC, to line out, with a .01uF ceramic to ground in between. This is same circuit found on some of the Parallax Propeller demo boards.