Non-volatile semiconductor memory device
US5428569A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 1993 |
| Grant date | Jun 27, 1995 |
| Priority date | — |
| Expiry date | Mar 29, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C16/04
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A non-volatile semiconductor memory device comprises: a plurality of memory cells for electrically rewriting data; a programming and erasing section for executing data writing programs and data erasing operation for the memory cells; a verifying section for discriminating whether a data is written in or erased from one of the memory cells properly whenever data are written to or erased from the memory cells; and an automatic control section for enabling the programming and erasing section to execute the data writing program and erasing operation again whenever the verifying section discriminates that data is not properly written to or erased from one of the memory cells, the data writing program or erasing operation being executed repeatedly by the number of times less than a user-defined maximum program execution or erasing operation number applied externally from the outside of the memory device. Further, the number of data writing and erasing operations can be outputted to the outside of the chip. Therefore, it is possible to optimize the limit of the data writing operation according to the chip samples and to detect the deterioration status of he chip externally from the chip. …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.