Flash / IC used in SD Cards.

Started by Jon S. November 9, 2004
I'm working on a project that will use a SD Card for file storage. 

We would also have some 'internal' filespace. So i thought of placing
a second memory on the PCB and on the same SPI bus. This would save
the work of writing a different driver.

Offcoarse i could add a second SD Card socket to my pcb, but i was
wondering if the chip used inside is available (Serial Flash ?) , so i
we could place such a chip directly on the pcb.

Anyone a clue what is inside these cards and if these cips are
available in small quantity's ?

Stijn
Jon S. schrieb:

> I'm working on a project that will use a SD Card for file storage. > > We would also have some 'internal' filespace. So i thought of placing > a second memory on the PCB and on the same SPI bus. This would save > the work of writing a different driver. > > Offcoarse i could add a second SD Card socket to my pcb, but i was > wondering if the chip used inside is available (Serial Flash ?) , so i > we could place such a chip directly on the pcb. > > Anyone a clue what is inside these cards and if these cips are > available in small quantity's ?
Have a look at Atmel's SerialFlash devices. (Guessing you don't need the security functions of the SD card.) -- Dipl.-Ing. Tilmann Reh Autometer GmbH Siegen - Elektronik nach Ma�. http://www.autometer.de
> We would also have some 'internal' filespace. So i thought of placing > a second memory on the PCB and on the same SPI bus. This would save > the work of writing a different driver. > > Offcoarse i could add a second SD Card socket to my pcb, but i was > wondering if the chip used inside is available (Serial Flash ?) , so i > we could place such a chip directly on the pcb. > > Anyone a clue what is inside these cards and if these chips are > available in small quantity's ? >
Quite often an Atmel ARM7 based ASIC and some parallel flash :-) The Dataflash (AT45DBxxx) are available up to 8 MBytes in size and will very soon be available in 16 MByte. The family is from 1 Mbit to 128 Mbit (256 Mbit later) and will soon be fully pin compatible. (With the new chips, there will be SOIC-8 footprint available for all parts including the 16 Mbyte) The major advantages of the dataflash is the simple interface (SPI) Fully documented interface (in the datasheet), No need to sign NDAs or pay out any license fees. The sectors are small (256-1024 bytes) and have additional bytes for CRC etc. You can buy Dataflash from any decent Atmel distributor. -- Best Regards Ulf at atmel dot com These comments are intended to be my own opinion and they may, or may not be shared by my employer, Atmel Sweden.