0

I want to buy a SSD, but I am confused as to how 3D NAND (that is now the latest and greatest) relate to MLC, TLC and QLC ?

Is there like 3D NAND TLC or 3D NAND QLC ? Or this 3D NAND completely separate from these ?

ng.newbie
  • 449
  • 1
  • 5
  • 16
  • 1
    this ought to help: https://www.enterprisestorageforum.com/hardware/slc-vs-mlc-vs-tlc-nand-flash/ and yes there is 3D NAND QLC. Keep in mind, there isn't a "Best"/"Greatest". all of these technologies optimize for a particular characteristic. SLC is still the most reliable and performant, but is the most costly by far, and has the lowest storage density for physical area. TLC is cheap and packs storage into a dense area but is the slowest, least robust and least reliable. – Frank Thomas May 02 '21 at 19:39

1 Answers1

2

3D NAND refers to the layout of the chip's memory cells, while MLC, TLC and QLC refer to technology of each cell.

For example, the NAND flash in Intel’s SSD D5-P4326 is referred to as 3D QLC. QLC, or quad-level cell technology, refers to each memory cell’s ability to save four bits of data across 15 different threshold voltages. 3D is a reference to the way memory cells are built.

Previously, cells were arranged side by side on a silicon substrate. As their density increased with new lithography processes, more of them could fit on a planar surface. But as it became increasingly difficult to scale along the x- and y-axis, manufacturers started organizing them vertically along the z-axis.

Taking as an example a 64 layers-tall flash device, 3D NAND enables here 64 times the cell density of planar memory. When adding QLC technology, that 64x is turned into 256x. That way, Intel’s 64-layer 3D NAND used in the SSD D5-P4326 can fit 1Tb density per die, for a higher-capacity SSD in the same form factor.

harrymc
  • 455,459
  • 31
  • 526
  • 924