What is the NAND Flash ?

NAND Flash, like many other types of memory, stores data in a large array of cells where each cell holds one or more bits of data. In a typical NNAND Flash device, a high voltage of 1.8V is applied to the control gate to draw electrons form the Si-Substrate to tunnel through the gate oxide into a polysilicon floating gate layer. To store one bit, two charge levels in the floating gate layer can be stored to distinguish between a "1" and a "0"

Multi level cells store additional charge levels within each bit cell.

A NAND Flash array is organized into many blocks. Each byte in one of these blocks can be individually written or programmed, but to write or programm the block, the single blocks must be pre erased. In an erased block, every bit is set to "1". A 2Gb SLC(Single level cell) NAND Flash memory device usually consists of 2048(128KB) blocks with 64 pages per block. Each page has 2112 bytes total, comprised of a 2048 byte data area and a 64 byte spare area for ECC, Wear Leveling information, and other software overhead functions.

The NAND Device Interface is 8 bit or 16 bit mode.