MLC meaning in Electronics ?

In electronics, a multi-level cell (MLC) is a memory cell capable of storing more than a single bit of information, compared to a single-level cell (SLC) which can store only one bit per memory cell. A memory cell typically consists of a single floating gate MOSFET (metal-oxide-semiconductor field-effect transistor), thus multi-level cells reduce the number of MOSFETs required to store the same amount of data as single-level cells.

Triple-level cells (TLC) and quad-level cells (QLC) are versions of MLC memory, which can store three and four bits per cell, respectively. The name "multi-level cell" is sometimes used specifically to refer to the "two-level cell". Overall, the memories are named as follows:

Typically, as the 'level' count increases, performance (speed and reliability) and consumer cost decrease; however this correlation can vary between manufacturers.

Examples of MLC memories are MLC NAND flash, MLC PCM (phase change memory), etc. For example, in SLC NAND flash technology, each cell can exist in one of the two states, storing one bit of information per cell. Most MLC NAND flash memory has four possible states per cell, so it can store two bits of information per cell. This reduces the amount of margin separating the states and results in the possibility of more errors. Multi-level cells which are designed for low error rates are sometimes called enterprise MLC (eMLC).

New technologies, such as multi-level cells and 3D Flash, and increased production volumes will continue to bring prices down.