发明授权
- 专利标题: Nonvolatile semiconductor memory device
- 专利标题(中): 非易失性半导体存储器件
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申请号: US11637026申请日: 2006-12-12
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公开(公告)号: US07450417B2公开(公告)日: 2008-11-11
- 发明人: Seiji Kaneko , Naoki Ueda
- 申请人: Seiji Kaneko , Naoki Ueda
- 申请人地址: JP Osaka
- 专利权人: Sharp Kabushiki Kaisha
- 当前专利权人: Sharp Kabushiki Kaisha
- 当前专利权人地址: JP Osaka
- 代理机构: Harness, Dickey & Pierce, PLC
- 优先权: JP2005-363000 20051216
- 主分类号: G11C11/34
- IPC分类号: G11C11/34 ; G11C16/04
摘要:
There is provided a nonvolatile semiconductor memory device capable of accelerating writing time and avoiding readout errors of information by eliminating variation in threshold voltage of unselected memory cells. In a nonvolatile semiconductor memory device having a memory cell array with memory cells capable of erasing and programming information, the memory cells store one data value selected from the same number of data values as programming distribution ranges, associated with that the electrical attribute belongs to any one of the more than one programming distribution ranges. The device comprises an erasure means for erasing the selected memory cell to be erased so that its electrical attribute belongs to a erasure distribution range not overlapping any of the programming distribution ranges and a programming means for programming an erased memory cell to be programmed so that its electrical attribute belongs to any one of the programming distribution ranges.
公开/授权文献
- US20070140017A1 Nonvolatile semiconductor memory device 公开/授权日:2007-06-21
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