发明授权
US08149607B2 Rewritable memory device with multi-level, write-once memory cells
有权
具有多级,一次写入存储单元的可重写存储器件
- 专利标题: Rewritable memory device with multi-level, write-once memory cells
- 专利标题(中): 具有多级,一次写入存储单元的可重写存储器件
-
申请号: US12643561申请日: 2009-12-21
-
公开(公告)号: US08149607B2公开(公告)日: 2012-04-03
- 发明人: Roy E. Scheuerlein , Luca Fasoli
- 申请人: Roy E. Scheuerlein , Luca Fasoli
- 申请人地址: US CA Milpitas
- 专利权人: SanDisk 3D LLC
- 当前专利权人: SanDisk 3D LLC
- 当前专利权人地址: US CA Milpitas
- 代理机构: Brinks Hofer Gilson & Lione
- 主分类号: G11C17/00
- IPC分类号: G11C17/00
摘要:
The embodiments described herein are directed to a memory device with multi-level, write-once memory cells. In one embodiment, a memory device has a memory array comprising a plurality of multi-level write-once memory cells, wherein each memory cell is programmable to one of a plurality of resistivity levels. The memory device also contains circuitry configured to select a group of memory cells from the memory array, and read a set of flag bits associated with the group of memory cells. The set of flag bits indicate a number of times the group of memory cells has been written to. The circuitry is also configured to select a threshold read level appropriate for the number of times the group of memory cells has been written to, and for each memory cell in the group, read the memory cell as an unprogrammed single-bit memory cell or as a programmed single-bit memory cell based on the selected threshold read level.
公开/授权文献
信息查询