公开(公告)号：US20180254090A1

公开(公告)日：2018-09-06

申请号：US15816546

申请日：2017-11-17

Applicant: SanDisk Technologies LLC

Inventor： Deepanshu Dutta ,  Idan Alrod ,  Huai-Yuan Tseng ,  Amul Desai ,  Jun Wan ,  Ken Cheah ,  Sarath Puthenthermadam

IPC: G11C16/34 ,  G11C16/16 ,  G11C16/26

CPC classification number: G11C16/3413 ,  G11C8/08 ,  G11C11/5642 ,  G11C16/08 ,  G11C16/16 ,  G11C16/26 ,  G11C16/3445 ,  G11C16/3459 ,  G11C29/021 ,  G11C29/028 ,  G11C2029/1202

Abstract: Techniques are provided for improving the accuracy of read operations of memory cells, where the threshold voltage of the memory cells can shift depending on the coupled up state of the word lines. In one approach, for a read operation, a representative word line voltage in a block is detected and a corresponding set of read voltages is selected. In another approach, a pre-read voltage pulse is applied to a selected word line in response to a read command, just prior to reading the selected cells. In another approach, a voltage pulse is periodically applied to each word line in a block to provide the word lines in a coupled up state. In another approach, a soft erase is performed after a read operation to prevent coupling up of the word lines.

公开(公告)号：US10229744B2

公开(公告)日：2019-03-12

申请号：US15816546

申请日：2017-11-17

Applicant: SanDisk Technologies LLC

Inventor： Deepanshu Dutta ,  Idan Alrod ,  Huai-Yuan Tseng ,  Amul Desai ,  Jun Wan ,  Ken Cheah ,  Sarath Puthenthermadam

IPC: G11C16/04 ,  G11C16/34 ,  G11C16/26 ,  G11C16/16 ,  G11C8/08 ,  G11C16/08 ,  G11C29/02 ,  G11C11/56 ,  G11C29/12

Abstract: Techniques are provided for improving the accuracy of read operations of memory cells, where the threshold voltage of the memory cells can shift depending on the coupled up state of the word lines. In one approach, for a read operation, a representative word line voltage in a block is detected and a corresponding set of read voltages is selected. In another approach, a pre-read voltage pulse is applied to a selected word line in response to a read command, just prior to reading the selected cells. In another approach, a voltage pulse is periodically applied to each word line in a block to provide the word lines in a coupled up state. In another approach, a soft erase is performed after a read operation to prevent coupling up of the word lines.

公开(公告)号：US10026486B1

公开(公告)日：2018-07-17

申请号：US15451186

申请日：2017-03-06

Applicant: SanDisk Technologies LLC

Inventor： Deepanshu Dutta ,  Idan Alrod ,  Huai-Yuan Tseng ,  Amul Desai ,  Jun Wan ,  Ken Cheah ,  Sarath Puthenthermadam

IPC: G11C16/04 ,  G11C16/34 ,  G11C16/26 ,  G11C16/16

Abstract: Techniques are provided for improving the accuracy of read operations of memory cells, where the threshold voltage of the memory cells can shift depending on the coupled up state of the word lines. In one approach, for a read operation, a representative word line voltage in a block is detected and a corresponding set of read voltages is selected. In another approach, a pre-read voltage pulse is applied to a selected word line in response to a read command, just prior to reading the selected cells. In another approach, a voltage pulse is periodically applied to each word line in a block to provide the word lines in a coupled up state. In another approach, a soft erase is performed after a read operation to prevent coupling up of the word lines.