Non-volatile RAM transferring data between ferro-electric capacitors and a memory cell
US5495437A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 5, 1994 |
| Grant date | Feb 27, 1996 |
| Priority date | — |
| Expiry date | Jul 5, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C14/00
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A non-volatile RAM circuit (10) uses ferro-electric capacitors (14, 16) to store data in a dormant state. Data is initially stored on the ferro-electric capacitors. The data stored on the ferro-electric capacitors is transferred to a memory cell (25) when the RAM circuit is powered up. Subsequent read operations after the power-up sequence obtain data from the memory cell instead of the ferro-electric capacitors. Any write operation during the power-up sequence is stored in the memory cell. When power is removed, the ferro-electric capacitors are updated with the present state of the memory cell. The endurance and data retention time of the ferro-electic capacitors increases by accessing data from the memory cell.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.