Non-volatile semiconductor memory device with diagnostic potential generator for individually checking whether memory cells are over-erased
US5854766A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 13, 1997 |
| Grant date | Dec 29, 1998 |
| Priority date | — |
| Expiry date | May 13, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C16/3404
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
When floating gate type memory transistors undesirably enter into an over-erased state, a diagnostic potential generator supplies a first diagnostic potential to a source line and second and third diagnostic potentials to non-selected word lines and a selected word line; the potential difference between the first diagnostic potential and the second diagnostic potential causes an over-erased memory transistor to be turned off, and the potential difference between the first diagnostic potential and the third diagnostic potential allows an over-erased memory transistor to turn on so as to identify each over-erased memory transistor by its row and column addresses.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.