Description These SD cards are highly integrated flash memories with serial and random access capability. It is accessible via a dedicated serial interface optimized for fast and reliable data transmission. This interface allows several cards to be stacked by through connecting their peripheral contacts. These SD cards are fully compatible to a new consumer standard, called the SD Card system standard define in the SD card System specification. The SD card system is a new mass-storage system based on innovations in semiconductor technology. It has been developed to provide an inexpensive, mechanically robust storage medium in card form for multimedia consumer applications. SD card allows the design of inexpensive players and drivers without moving parts. A low power consumption and a wide supply voltage range favors mobile, battery-powered application such as audio players, organizers, palmtops, electronic books, encyclopedia and dictionaries. Using very effective data compression schemes such as MPEG, the SD card will deliver enough capacity for all kinds of multimedia data.