AT45DB321E-SHF-T

The AT45DB321E is a 2.3 V minimum, serial-interface sequential access Flash memory ideally suited for a wide
variety of digital voice, image, program code, and data storage applications. The AT45DB321E also supports the
RapidS serial interface for applications requiring very high speed operation. Its 34,603,008 bits of memory are
organized as 8,192 pages of 512 bytes or 528 bytes each. In addition to the main memory, the AT45DB321E also
contains two SRAM buffers of 512/528 bytes each. The buffers allow receiving of data while a page in the main
memory is being reprogrammed. Interleaving between both buffers can dramatically increase a system’s ability to
write a continuous data stream. Also, the SRAM buffers can be used as additional system scratch pad memory,
and E2PROM emulation (bit or byte alterability) can be easily handled with a self-contained three step readmodify-write operation.
Unlike conventional Flash memories that are accessed randomly with multiple address lines and a parallel
interface, the Renesas Electronics DataFlash® uses a serial interface to sequentially access its data. The simple
sequential access dramatically reduces active pin count, simplifies hardware layout, increases system reliability,
minimizes switching noise, and reduces package size. The device is optimized for use in many commercial and
industrial applications where high-density, low-pin count, low-voltage, and low-power are essential.
For simple in-system re-programmability, the AT45DB321E does not require high input voltages for programming.
The device operates from a single 2.3 V to 3.6 V power supply for the erase and program and read operations.
The AT45DB321E is enabled through the Chip Select pin (CS) and accessed via a 3-wire interface consisting of
the Serial Input (SI), Serial Output (SO), and the Serial Clock (SCK).
All programming and erase cycles are self-timed.