Adaptive dynamic reading of flash memories
US8289781B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 20, 2011 |
| Grant date | Oct 16, 2012 |
| Priority date | — |
| Expiry date | Feb 20, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C2211/5634
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Each of a plurality of flash memory cells is programmed to a respective one of L≧2 threshold voltage states within a threshold voltage window. Values of parameters of threshold voltage functions are adjusted in accordance with comparisons of the threshold voltages of some or all of the cells to two or more of m≧2 threshold voltage intervals within the threshold voltage window. Reference voltages for reading the cells are selected based on the values. Alternatively, the m threshold voltage intervals span the threshold voltage window, and respective threshold voltage states are assigned to the cells based on numbers of cells whose threshold voltages are in the intervals, without re-reading the cells.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.