The Secure Digital (SD) Memory Card is a flash memory storage device
designed to meet the security, capacity, performance and environmental
requirements inherent in emerging audio and video consumer electronics
devices. The SD Card design is highly leveraged from the existing
MultiMediaCard specification. Key enhancements over the MultiMediaCard
include cryptographic security for protection of copyrighted data, up
to a 4X improvement in the data transfer rate and a user-selectable write protect
switch on the card casing. Improvements in Electro Static Discharge (ESD)
tolerance are also provided through enhancements to the card's protective
casing. The SD Card is ideally suited for portable digital devices such as audio
players, digital still cameras, digital video camcorders, handheld PCs and cell
phones. The card is slightly thicker than a MultiMediaCard allowing it to contain
more memory for higher data capacity while maintaining the smallest area
profile in the market. Host systems designed for the SD Card will allow reading
and writing of existing MultiMediaCards thus ensuring that existing user data
can be easily migrated to, and used in, next generation systems.