Measuring cell damage for wear leveling in a non-volatile memory
US9329948B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 15, 2012 |
| Grant date | May 3, 2016 |
| Priority date | — |
| Expiry date | Sep 15, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2212/7211
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An NVM controller measures cell damage for wear leveling in an NVM, thus improving performance, reliability, lifetime, and/or cost of a storage sub-system, such as an SSD. In a first aspect, the controller determines that an error reading a page of NVM was caused by cell damage and/or cell leakage. The controller reprograms and immediately reads back the page, detecting that the error was caused by cell damage if an error is detected during the immediate read. In a second aspect, the cell damage is tracked by updating cell damage counters for pages and/or blocks of NVM. In a third aspect, wear leveling is performed based at least in part upon measured cell damage for pages and/or blocks of NVM.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.