Secure Digital

SD=Secure Digital

SD card

MMC with added DRM like functions.

Physical size

Version:	Name:
1.0/1.1	SD
2.0	SD-HC (HC=High capacity)

SD 1.0 (October 2001)
- Complete Standard NDA & $$$
- Simplified Standard released 2005
- Based on MMC Standard
- One device on bus
- 4bit 25MHz bus (12.5MB/ s)
- Alternative SPI bus interface
- 16MB- 2GB (4GB available)
SD 2.0 (April 2006)
- SDHC (4GB- 32GB)
- Optional 8- bit bus
- 3 speed classes(2MB/ s, 4MB/ s, 6MB/ s)

 ___________  
/ ||||||||| |
||1       8 |
|9          |

Pin	Name	Dir	Description
1	CD/DAT3	^PP)	Card Detect/Data Line 3
2	CMD	^PP)	Command Line
3	VSS1		Ground
4	Vdd		Voltage Supply [2.7v or 3.6v]
5	Clock		Clock
6	Vss2		Ground
7	DAT0	^PP)	Data Line 0
8	DAT1	^PP)	Data Line 1
9	DAT2	^PP)	Data Line 2

Note: Direction is memory card relative to host
^PP) Output is Push-pull.

Pin	Name	Dir	Description
1	/CS		Chip Select/Slave Select (SS)
2	DI	^PP)	Master Out/Slave In (MOSI)
3	VSS		Supply voltage ground
4	VDD		Supply voltage
5	CLK		Clock (SCK)
6	VSS		Supply voltage ground
7	DO	^PP)	Master In/Slave Out (MISO)
8	IRQ		not connected or IRQ
9	NC		not connected

Note: Direction is memory card relative to host
^PP) Push-pull.