Memory having write current ramp rate control
US6657889B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2002 |
| Grant date | Dec 2, 2003 |
| Priority date | — |
| Expiry date | Jun 28, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C11/15
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A magnetoresistive random access memory (MRAM) has separate read and write paths. Switchable current mirrors, each having multiple series-connected stages, receive a common reference current. A timing circuit provides control signals to word and bit decoders and to the switchable current mirrors to selectively complete current paths through a predetermined write word line and a predetermined write bit line. Bit lines are connected together at a common end, and word lines are connected together at a common end. By precharging a common rail having multiple write bit lines connected together, the write noise immunity is improved and current spikes are minimized. Groups of bit lines may be connected via a metal option to adjust a transition time of a programming current.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.