Patent · US Active

Threshold optimization for flash memory

US8848439B2 · kind B2 · utility

3Cited by
1References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 24, 2012
Grant dateSep 30, 2014
Priority date
Expiry dateJan 10, 2033

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C16/3404
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Described embodiments provide enhanced read accuracy of a multi-level cell (MLC) flash memory. A read request for desired cells is received by a media controller of the memory. The media controller sets m thresholds to initial values, each threshold corresponding to a cell voltage level of the memory, and measures the cell voltage level of a given cell. For each of the desired cells of the memory, the media controller iteratively, until the measured cell voltage level converges on one of the thresholds, compares the measured cell voltage level to the thresholds. If the measured cell voltage level does not converge on one of the thresholds, the media controller updates the thresholds, remeasures the cell voltage level and compares the remeasured cell voltage level to the updated thresholds. Once the measured cell voltage level converges on a threshold, the media controller determines a binary level of the cell.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.