Nonvolatile memory with cluster-erase flash capability and solid state file apparatus using the same
Patent 5457658 Issued on October 10, 1995. Estimated Expiration Date: 
February 23, 2014. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
February 23, 2014. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesMethod and circuitry for erasing a nonvolatile semiconductor memory incorporating row redundancy Patent #: 5327383 InventorsApplicationNo. 200343 filed on 02/23/1994US Classes:365/218, Erase365/185.29, Erase711/102, Solid-state read only memory (ROM)711/103, Programmable read only memory (PROM, EEPROM, etc.)711/206Translation tables (e.g., segment and page table or map)ExaminersPrimary: Fears, Terrell W.Attorney, Agent or FirmInternational ClassG11C 013/00Foreign Application Priority Data1993-02-24 JPAbstractA nonvolatile memory with cluster-erase flash capability. A cluster information sector is included in each of N clusters, the cluster information sector of each cluster being written with the sequence number assigned to the cluster so that no two clusters have the same sequence number. When erasing a given sector, a controller saves its sequence number prior to erasure. Then, when initializing a given erased sector, the controller sets its sequence number to a value greater than the current maximum sequence number. The controller writes user data to sectors other than the cluster information sector for the cluster thus initialized according to their address sequence. Accordingly, an invalid sector can be distinguished from a valid sector without using an overwrite approach. | |
