Patent Number: 8,879,319

Title: Re-writing scheme for solid-state storage devices

Abstract: A multi-level cell flash memory storage device has cells wherein different charge levels represent different information. The storage device can read stored charge from one or more cells, store a rewrite generation value for a group of a plurality of cells in a block of cells, and write to cells, wherein writing to one or more cells without an erase includes an increment of the rewrite generation value, and includes circuitry for reading from cells, including circuitry for reading the rewrite generation value. The storage device can include circuitry for reading from cells includes within the multi-level cell flash memory storage device logic for calculating a stored value of the cells using the rewrite generation value and relative levels of charge on a plurality of cells. The storage device can track hot addresses and cold addresses and perform static or dynamic wear leveling based on accumulated rewrite generation values.

Inventors: Cassuto; Yuval (Lausanne, CH), Zhang; Luoming (Ecublens, CH), Shokrollahi; M. Amin (Preverenges, CH)

Assignee: Ecole Polytechnique Federale de Lausanne (EPFL)

International Classification: G11C 16/04 (20060101)

Expiration Date: 2019-11-04 0:00:00