Multi-level cell (MLC) NAND type solid-state hard disk, read-write control method and flash memory controller

Abstract

The invention is suitable for the technical field of storage, provides a multi-level cell (MLC) NAND type solid-state hard disk, a read-write control method and a flash memory controller, and is used for enabling an MLC type flash memory chip to be simulated into a single-level cell (SLC) type flash memory chip. The read-write control method includes: a physical page of the MLC type flash memory chip is mapped to two logic pages of the same size, one logic page is formed by least significant bit mapping in the physical page, and the other logic page is composed by most significant bit mapping in the physical page. When the MLC type flash memory chip is read and wrote, only one of the two logic pages of the same size is obtained to be read and wrote. The MLCNAND type solid-stage hard disk can be simulated into an SLC NAND type solid-state hard disk, and performance of the MLC NAND type solid-state hard disk is improved.

Description

technical field [0001] The invention relates to the field of storage technology, in particular to an MLC (Multi-Level Cell, multi-level cell) NAND solid-state hard disk, a read-write control method, and a flash memory controller. Background technique [0002] NAND flash memory can be divided into SLC (Single-Level Cell, single-level unit) NAND flash memory and MLC NAND flash memory according to the number of bits that can be stored in each storage unit. [0003] Each memory cell of the SLC NAND flash memory chip can have two states: high voltage or low voltage, representing data 0 and 1 respectively, such that a memory cell can represent a data bit. A physical page is composed of multiple physical storage units, and the physical page can represent the same number of bits, that is, a logical page. [0004] Each memory cell of an MLC NAND flash memory chip can have 4 voltage states. MLC represents different data according to different voltage values. figure 1 It is a schema...

AI Technical Summary

Problems solved by technology

[0005] Among them, the pure SLC NAND flash memory has the advantages of fast read / write speed, long life, better performance, and more erasing times, but it also has the disadvantages of high price and low storage capacity; although SLC NAND flash memory has a larger capacity, and the price is cheap, but its erasure is limited, the read and write speed is slow, the performance is low and the life is short

Therefore, in the actual use of the existing MLC NAND flash memory, there are obviously inconveniences and defects, so it is necessary to improve

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