Product manual

3-3 SanDisk miniSD Card Product Manual, Rev. 1.1 © 2003 SANDISK CORPORATION
Figure 3-2. SD Card Architecture
3.2. SD Bus Topology
The SD bus has six communication lines and three supply lines:
CMD—Command is a bi-directional signal. (Host and card drivers are operating in push pull mode.)
DAT0-3—Data lines are bi-directional signals. (Host and card drivers are operating in push pull
mode.)
CLK—Clock is a host to cards signal. (CLK operates in push pull mode.)
VDD—VDD is the power supply line for all cards.
VSS [1:2]—VSS are two ground lines.