概觀
The IS34/35ML2G084 is a 256Mx8bit with spare 8Mx8bit capacity. The device is offered in 3.3V Vcc
Power Supply. Its NAND cell provides the most cost-effective solution for the solid state mass storage
market. The memory is divided into blocks that can be erased independently so it is possible to preserve
valid data while old data is erased.
The device contains 2,048 blocks, composed by 64 pages consisting in two NAND structures of 32
series connected Flash cells. A program operation allows to write the 2,112-Byte page in typical 300us
and an erase operation can be performed in typical 3ms on a 128K-Byte for X8 device block.
Data in the page mode can be read out at 25ns cycle time per Word. The I/O pins serve as the ports for
address and command inputs as well as data input/output.
The copy back function allows the optimization of defective blocks management: when a page program
operation fails, the data can be directly programmed in another page inside the same array section
without the time consuming serial data insertion phase.
The cache program feature allows the data insertion in the cache register while the data register is
copied into the Flash array.
This pipelined program operation improves the program throughput when long files are written inside
the memory. A cache read feature is also implemented. This feature allows to dramatically improving
the read throughput when consecutive pages have to be streamed out. This device includes extra
feature: Automatic Read at Power Up.