Non-volatile semiconductor memory device
    52.
    发明授权
    Non-volatile semiconductor memory device 失效
    非易失性半导体存储器件

    公开(公告)号:US5777921A

    公开(公告)日:1998-07-07

    申请号:US821024

    申请日:1997-03-19

    CPC分类号: G11C7/00 G11C11/22 G11C11/223

    摘要: A non-volatile semiconductor memory device includes a plurality of memory cells each including a capacitor as a memory element, the capacitor sandwiching a ferroelectric member. The non-volatile semiconductor memory device further includes: a first counter for counting the number of write accesses and read accesses for writing or reading first logic data to each one of the plurality of memory cells; a second counter for counting the number of write accesses and read accesses for writing or reading second logic data to the memory cell; and a refresh control circuit for performing, when either a first value counted by the first counter or a second value counted by the second counter exceeds a predetermined value, a refresh operation by applying electric fields for causing a polarization state of the ferroelectric member of the capacitor to make a complete round on a hysteresis curve of the ferroelectric member in a corresponding one of the plurality of memory cells for which the first or second value counted by the first counter or the second counter has exceeded the predetermined value.

    摘要翻译: 非挥发性半导体存储器件包括多个存储单元,每个存储单元包括作为存储元件的电容器,夹着铁电元件的电容器。 所述非易失性半导体存储器件还包括:第一计数器,用于对所述多个存储单元中的每一个写入或读取第一逻辑数据的写访问次数和读访问数进行计数; 第二计数器,用于计数用于将第二逻辑数据写入或读取到存储器单元的写访问次数和读访问次数; 以及刷新控制电路,用于当通过第一计数器计数的第一值或由第二计数器计数的第二值超过预定值时执行刷新操作,通过施加电场来引起铁电元件的极化状态 电容器,用于在由第一计数器或第二计数器计数的第一或第二值超过预定值的多个存储单元中的对应的一个存储单元中的铁电元件的滞后曲线上完成一整圆。

    Electrical discharge machine with automatic filtering
    53.
    发明授权
    Electrical discharge machine with automatic filtering 失效
    放电机具有自动过滤功能

    公开(公告)号:US5386094A

    公开(公告)日:1995-01-31

    申请号:US2414

    申请日:1993-01-08

    IPC分类号: B23H1/10 B23H5/14 B23H7/36

    CPC分类号: B23H1/10 B23H7/36

    摘要: An electrical discharge machine having an electrode and workpiece contained within a dielectric-filled machining tank for machining in response to the application of discharge current. One or more auxiliary tanks that contain additional dielectric fluid are connected to the machining tank by a plurality of fluid flow paths that contain various combinations of filters, valves and pumps. The filters may be of different filtering capacity for serving different machining operations, e.g., roughing and finishing. The operation of the valves to provide filtering appropriate to the current machining conditions is based on detected or predetermined machining conditions such as sludge grain diameter, fluid pressure, sludge quantity, electrode and workpiece material composition and discharge current levels.

    摘要翻译: 一种放电机,其具有电极和工件,该电极和工件包含在电介质填充的加工槽内,用于响应于施加放电电流进行加工。 包含附加介电流体的一个或多个辅助罐通过包含过滤器,阀和泵的各种组合的多个流体流动路径连接到加工槽。 过滤器可以具有不同的过滤能力,用于服务不同的加工操作,例如粗加工和精加工。 根据检测到或预定的加工条件,例如污泥粒径,流体压力,污泥量,电极和工件材料组成以及放电电流水平,根据当前加工条件提供过滤器的操作。