microSD

microSD Pinout, SD Mode

Pin #	Pin Name	Signal Function
1	DAT2	Data Bit 2
2	CD/DAT3	Card Detect / Data Bit 3
3	CMD	Command Line
4	Vdd	Supply Voltage 2.7v / 3.6v
5	CLK	Clock
6	Vss	Ground
7	DAT0	Data Bit 0
8	DAT1	Data Bit 1

microSD Pinout, SPI Mode

Pin #	Pin Name	Signal Function
1	NC	No Connect
2	/CS	Chip Select
3	DI	Master Out/Slave In (MOSI)
4	Vdd	Supply Voltage 2.7v / 3.6v
5	CLK	Clock
6	Vss	Ground
7	DO	Master In/Slave Out (MISO)
8	RSV	Reserved

The graphic to the right shows:
The SD card, 32mm x 24mm
The miniSD card, 21.5 x 20mm
The microSD card, 15mm x 11mm
Slot adaptors may be purchased to allow a smaller SD
card type to plug into a larger type.

The MicroSD form factors picture is used under GNU License

The Secure Digital card dimensions are: 24mm wide x 32mm long. The standard width is 2.1mm, while the Thin SD Memory Card has a width 1.4mm.

Secure Digital Pinout

Pin #	Pin Name	SD Signal Function SD Mode	SPI Signal Function SPI Mode
1	DAT3/CS	Data Line 3	Chip Select/Slave Select [SS]
2	CMD/DI	Command Line	Master Out/Slave In [MOSI]
3	VSS1	Ground	Ground
4	Vdd	Voltage Supply [2.7v or 3.6v]	Voltage Supply [2.7v or 3.6v]
5	Clock	Clock	Clock [SCK]
6	Vss2	Ground	Ground
7	DAT0/D0	Data Line 0	Master In Slave Out [MISO]
8	DAT1/IRQ	Data Line 1	Unused or IRQ
9	DAT2/NC	Data Line 2	Unused

miniSD Pinout

Pin #	Pin Name	SD Signal Function SD Mode	SPI Signal Function SPI Mode
1	CD/DAT3	Chip Detect/Data Line 3	Chip Select
2	CMD	Command Line	Data In [DI]
3	VSS1	Ground	Ground
4	Vdd	Voltage Supply [2.7v or 3.6v]	Voltage Supply [2.7v or 3.6v]
5	Clock	Clock	Clock [SCK]
6	Vss2	Ground	Ground
7	DAT0	Data Line 0	Data Out [DO]
8	DAT1	Data Line 1	Unused
9	DAT2	Data Line 2	Unused
10	NC	For future use	For future use
11	NC	For future use	For future use