Patent
Non-volatile ferroelectric SRAM
| العنوان: | Non-volatile ferroelectric SRAM |
|---|---|
| Patent Number: | 6,996,000 |
| تاريخ النشر: | February 07, 2006 |
| Appl. No: | 10/961429 |
| Application Filed: | October 07, 2004 |
| مستخلص: | A non-volatile SRAM memory comprising a plurality of memory cells, each memory cell including a SRAM memory cell portion and a ferroelectric memory cell portion including a ferroelectric element, the ferroelectric memory cell portion including a switch system for permitting the ferroelectric element to be isolated from the ferroelectric elements in all other memory cells. |
| Inventors: | Chen, Zheng (Colorado Springs, CO, US); Paz de Araujo, Carlos A. (Colorado Springs, CO, US); McMillan, Larry D. (Colorado Springs, CO, US) |
| Assignees: | Symetrix Corporation (Colorado Springs, CO, US), Matsushita Electric Industrial Co., Ltd. (Osaka, JP) |
| Claim: | 1. A non-volatile memory comprising a plurality of memory cells, each memory cell including: a SRAM memory cell portion and a ferroelectric memory cell portion including a ferroelectric element; said memory including a data transfer circuit for transferring data from said SRAM cell portion to said ferroelectric memory cell portion when said memory is turned off and for transferring data from said ferroelectric memory cell portion to said SRAM memory cell when said memory is turned on; and said ferroelectric memory cell portion including a switch system for isolating said ferroelectric element from the ferroelectric elements in all other said memory cells when said data is not being transferred. |
| Claim: | 2. A non-volatile memory as in claim 1 wherein said ferroelectric element is a capacitor. |
| Claim: | 3. A non-volatile memory as in claim 1 wherein said switch system comprises a transistor. |
| Claim: | 4. A non-volatile memory as in claim 1 wherein each of said ferroelectric memory cell portions include a first ferroelectric capacitor, a second ferroelectric capacitor, a first switch and a second switch, and wherein said first switch isolates said first ferroelectric capacitor and said second switch isolates said second ferroelectric capacitor. |
| Claim: | 5. A non-volatile memory as in claim 4 wherein said first ferroelectric capacitor and said first switch are connected in parallel, and said second ferroelectric capacitor and said second switch are connected in parallel. |
| Claim: | 6. A non-volatile memory cell as in claim 4 wherein said first ferroelectric capacitor and said first switch are connected in series, and said second ferroelectric capacitor and said second switch are connected in series. |
| Claim: | 7. A non-volatile memory as in claim 1 wherein said memory includes a plate line and said switch is connected between said ferroelectric element and said plate line. |
| Claim: | 8. A non-volatile memory comprising a plurality of memory cells, each memory cell including a SRAM memory cell portion and a ferroelectric memory cell portion including a ferroelectric element, said ferroelectric memory cell portion including a switch system for permitting said ferroelectric element to be isolated from the ferroelectric elements in all other of said memory cells. |
| Claim: | 9. A non-volatile memory as in claim 8 wherein said ferroelectric element is a capacitor. |
| Claim: | 10. A non-volatile memory as in claim 8 wherein said switch system comprises a transistor. |
| Claim: | 11. A non-volatile memory comprising a plurality of memory cells, each memory cell including: a SRAM memory cell portion and a ferroelectric memory cell portion including a ferroelectric element; said memory including a data transfer circuit for transferring data from said SRAM cell portion to said ferroelectric memory cell portion when said memory is turned off and for transferring data from said ferroelectric memory cell portion to said SRAM memory cell when said memory is turned on; and said ferroelectric memory cell portion including a switch system for creating a short circuit across said ferroelectric element when said SRAM portion is operating normally. |
| Claim: | 12. A non-volatile memory as in claim 11 wherein said ferroelectric element is a capacitor. |
| Claim: | 13. A non-volatile memory as in claim 12 wherein said switch system comprises a transistor. |
| Claim: | 14. A method of operating a non-volatile SRAM memory cell in a memory containing a plurality of said cells, said method comprising: providing a SRAM memory cell portion and a ferroelectric memory cell portion including a ferroelectric element; transferring data between said SRAM memory cell portion and said ferroelectric memory cell portion; and isolating said ferroelectric element from all other ferroelectric elements in said memory when said data is not being transferred. |
| Claim: | 15. A method as in claim 14 wherein said ferroelectric element is a ferroelectric capacitor having two electrodes, said method further including shorting out the two electrodes of said ferroelectric element while said SRAM portion is operating normally. |
| Current U.S. Class: | 365/154 |
| Patent References Cited: | 4809225 February 1989 Dimmler et al. 6731530 May 2004 Miwa et al. 2004/0141363 July 2004 Ohtsuka et al. 2004/0196689 October 2004 Ohtsuka et al. |
| Primary Examiner: | Le, Vu A. |
| Attorney, Agent or Firm: | Patton Booge LLP |
| رقم الانضمام: | edspgr.06996000 |
| قاعدة البيانات: | USPTO Patent Grants |
| الوصف غير متاح. |