Nonvolatile semiconductor memory device
US9305637B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 2014 |
| Grant date | Apr 5, 2016 |
| Priority date | — |
| Expiry date | May 22, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C16/3459
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A nonvolatile semiconductor memory device includes a memory cell array having nonvolatile memory cells in which one of multiple values is programmable therein by setting one of a plurality of threshold values therein and a control circuit that performs a writing operation on the memory cells. The writing operation performed by the control circuit includes a pre-programming verification operation to determine a threshold level of a memory cell in an erasure state, and a program operation in which a program voltage is selected from a plurality of program voltages on the basis of a determination result of the pre-programming verification operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.