Efficient search for optimal read thresholds in flash memory
US9697075B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 8, 2015 |
| Grant date | Jul 4, 2017 |
| Priority date | — |
| Expiry date | Nov 5, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C16/28
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method includes storing data encoded with an ECC in a group of memory cells by writing respective storage values to the memory cells. Multiple sets of readout results are read from the memory cells by comparing the storage values to one or more threshold combinations, each including multiple read thresholds. A plurality of partial syndromes of the ECC is computed, each partial syndrome computed over the readout results that were read using a respective threshold combination. A respective syndrome is calculated for each threshold combination, in at least a subset of all possible threshold combinations, based on one or more of the partial syndromes associated with that threshold combination. A preferred threshold combination is selected, from among the threshold combinations, for which a weight of the respective syndrome is minimal, by processing less than all the partial syndromes associated with all the possible threshold combinations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.