Non-volatile semiconductor memory device capable of storing multi-value data in each memory cell
US5412601A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 30, 1993 |
| Grant date | May 2, 1995 |
| Priority date | — |
| Expiry date | Aug 30, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C2211/5642
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An electrically erasable non-volatile semiconductor memory device comprising a plurality of row lines and column lines, a plurality of memory cells connected in a matrix to the plurality of row lines and column lines, a selection circuit for selecting a desired one of the plurality of memory cells, and write-control circuit for writing data into the plurality of memory cells. The write-control circuit is adapted to preset at least four voltage signals having different voltage values, and to select one of four voltage signals according to a data signal externally applied thereto and applying the selected voltage signal to the selected memory cell. Also included is read-control circuit for reading out data written into the selected memory cell and converting the data read-out from the selected memory cell into a data signal corresponding to one of the four voltage signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.