“OK, this is a pretty well made SD breakout board - but, its not perfect. I confirm that it works perfectly well using the 3V3 supply. I have not tried the 5V supply. The only problem I have with it, is that like ALL the other SD breakout boards I have ever used, the DO (MISO) line is not tri-state. Meaning, when you de-select the board by raising SS, the MOSI line does not go "open circuit". This prevents you from using other SPI devices the same bus. The workaround is easy though. Just direct the MISO signal though a tri-state buffer (eg CD74HC125E) before connecting it to your microcontroller. Connect the SS pin of the SD module to the same SS pin of the tri-state buffer. Then, you can have the SD card working with any other device (like a camera in my case), and it all works happily together!”
