NAND Flash

NAND FLASHdevices, available in 128Mb to 2Tb densities, are used to store data and code. Low-density NAND flash is ideal for applications like STBs, digital televisions (DTVs), and DSCs while high-density NAND flash is most commonly used in data-heavy applications like SSDs, tablets, and USB drives. There is a continuous effort to reduce the cost/GB of NAND devices, so device life cycles tend to be shorter with more frequent process lithography shrinks. NAND requires a controller, either internal or external, and specific firmware for error code correction (ECC), bad block management, and wear leveling.

There are two primary types of NAND: raw and managed. Raw NAND comes in different flavors, including single-level cell (SLC), multilevel cell (MLC), triple-level cell (TLC) and quad-level cell (QLC). Raw NAND requires external management but is the lowest cost/GB NAND flash available. Managed NAND incorporates memory management into the package, simplifying the design-in process.