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By smcpeak
#192154
Hello,

I have a hardware related question regarding the Sparkfun Level Shifting microSD Breakout board "DEV-13743".

The schematic shows a 100K pull-up resistor from the CD1 pin to Vcc. I understand that this pin is floating when a card is inserted and the pull-up resistor would result in a high voltage that the host processor could use to detect the card's presence. I think the pin is tied to ground when the card is removed. However does this pin NOT contact the micro SD card itself? I understand that a micro SD card supply voltage should be no more then 3.3V. Since the CD pin is pulled to Vcc on the schematic I am guessing that this pin does not contact the micro SD card but would like to confirm. For my design Vcc will be 5V.

Thank you.