Memory device having memory cells capable of four states
US6483734B1 · kind B1 · utility
139Cited by
19References
18Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 26, 2001 |
| Grant date | Nov 19, 2002 |
| Priority date | — |
| Expiry date | Nov 26, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C2216/26
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A memory device includes memory cells having a re-writeable element and a write-once element in series with the re-writeable element. The re-writeable element is programmable between a high resistance state and a low resistance state. The write-once element can be an anti-fuse element that is programmable from a high resistance state to a low resistance state, or a fuse element that is programmable from a low resistance state to a high resistance state. The two possible states for the re-writeable element and the two possible states for the write-once element allow the memory cells to store four different bits.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.