Nonvolatile semiconductor memory device
US7286401B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 3, 2004 |
| Grant date | Oct 23, 2007 |
| Priority date | — |
| Expiry date | Jun 21, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C16/349
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Disclosed here is a nonvolatile semiconductor memory device used to prevent data loss that might occur in unselected memory cells due to a disturbance that might occur during programming/erasing in/from those memory cells. In the nonvolatile semiconductor memory device, the number of programming/erasing operations performed in a data storage block over a programming/erasing unit of the subject nonvolatile memory is recorded in an erasing/programming counter EW CT provided in each data storage block. When the value of the erasing/programming counter reaches a predetermined value, the data storage block corresponding to the erasing/programming counter is refreshed. In the refreshing operation, the data in the data storage block is stored in a temporary storing region provided in the data storage block, then the data in a temporary storing region of the data storage area is erased and the data stored temporarily is programmed in the data storage block again.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.