Storage device, memory controller and memory control method
US9171629B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 5, 2014 |
| Grant date | Oct 27, 2015 |
| Priority date | — |
| Expiry date | Sep 5, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C2211/5641
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
According to one embodiment, a storage device comprises a nonvolatile memory and a memory controller that performs reading and writing data from and into the nonvolatile memory. A number, not being 2n, of threshold areas can be set in the memory cells of the nonvolatile memory. The memory controller performs first writing based on first data value assignment, which sets 2n data values to correspond to 2n threshold areas, in first-time writing into a first memory cell of the nonvolatile memory and performs second writing on the first memory cell after the first writing without erasing data based on second data value assignment, which sets 2n data values to correspond to 2n threshold areas including threshold areas not used in the first data value assignment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.