Patents by Inventor Guirong Liang

Guirong Liang has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20240087650
    Abstract: A storage device is disclosed herein. The storage device comprises: a non-volatile memory, where the non-volatile memory includes a block of N wordlines partitioned into a plurality of sub-blocks; and control circuitry coupled to the N wordlines. The control circuitry is configured to: determine a program status of an unselected sub-block of the plurality of sub-blocks before performing an operation on a selected sub-block of the plurality of sub-blocks; based on determining that the program status of the unselected sub-block is programmed, perform a precharge operation including applying a first precharge time; and based on determining that the program status of the unselected sub-block is not programmed, perform a precharge operation including applying a second precharge time, wherein the first precharge time is for a longer period than the second precharge time.
    Type: Application
    Filed: September 8, 2022
    Publication date: March 14, 2024
    Applicant: SanDisk Technologies LLC
    Inventors: Han-Ping Chen, Guirong Liang
  • Publication number: 20240079062
    Abstract: The memory device includes at least one memory block with source and drain sides and a plurality of memory cells arranged in a plurality of word lines. The word lines are arranged in a plurality of independently programmable and erasable sub-blocks. Control circuitry is configured to program the memory cells of a selected sub-block and determine a location of the within the at least one memory block and determine a programming condition of at least one unselected sub-block. The control circuitry is also configured to program at least one word line in the selected sub-block in a plurality of program loops that include pre-charging processes. The control circuitry pre-charges a plurality of channels from either the source or drain side based on at least one of the location of the selected sub-block within the memory block and the programming condition of the at least one unselected sub-block.
    Type: Application
    Filed: September 6, 2022
    Publication date: March 7, 2024
    Applicant: SanDisk Technologies LLC
    Inventors: Jiacen Guo, Han-Ping Chen, Henry Chin, Guirong Liang, Xiang Yang
  • Patent number: 11887674
    Abstract: A memory apparatus and method of operation is provided. The apparatus includes memory cells each connected to one of a plurality of word lines. The memory cells are disposed in strings coupled to one of a plurality of bit lines and are configured to retain a threshold voltage corresponding to one of a plurality of data states. A control means is configured to read each of the memory cells in a read operation. For each one of the memory cells, the control means is also configured to offset at least one of a bit line settling time and a kick voltage during the read operation based on a probability of at least one neighboring one of the plurality of bit lines being coupled to the memory cells retaining the threshold voltage corresponding to a different one of the plurality of data states than the one of the memory cells.
    Type: Grant
    Filed: March 29, 2022
    Date of Patent: January 30, 2024
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Yanjie Wang, Guirong Liang, Xiaoyu Che, Yi Song
  • Publication number: 20230368844
    Abstract: A method of operating a non-volatile semiconductor memory device is disclosed. The method comprises: during a first pre-read cycle of a read operation, ramping up a control signal on a wordline selected for the read operation to a first target pre-read voltage and ramping up a control signal on a drain-side select (SGD) transistor of an unselected string of the plurality of strings to a second target pre-read voltage. The method further comprises during a second pre-read cycle of the read operation, ramping down the control signal on the wordline to a target read voltage and ramping down the control signal on the SGD transistor of the unselected string to a third target pre-read voltage after a delay period after the triggering edge of the second pre-read cycle.
    Type: Application
    Filed: May 11, 2022
    Publication date: November 16, 2023
    Applicant: SanDisk Technologies LLC
    Inventors: Yanjie Wang, Guirong Liang
  • Publication number: 20230326531
    Abstract: Technology is disclosed herein for a memory system having a dynamic supply voltage to sense amplifiers. In an aspect, the supply voltage has a higher magnitude when charging inhibited bit lines during a program operation and a lower magnitude when verifying/sensing memory cells. Reducing the magnitude of the supply voltage saves power and/or current. However, if the lower magnitude were used when the inhibited bit lines are charged during the program operations, some of the memory cells that should be inhibited from programming might experience at least some programming. Using the higher magnitude supply voltage during bit line charging of the program operation assures that the inhibited bit lines are charged to a sufficient voltage to keep drain side select gates of NAND strings off so that the NAND channel will boost properly to inhibit programming of such memory cells.
    Type: Application
    Filed: April 11, 2022
    Publication date: October 12, 2023
    Applicant: SanDisk Technologies LLC
    Inventors: Yanjie Wang, Ohwon Kwon, Kou Tei, Tai-Yuan Tseng, Yasue Yamamoto, Yonggang Wu, Guirong Liang
  • Publication number: 20230317174
    Abstract: A memory apparatus and method of operation is provided. The apparatus includes memory cells each connected to one of a plurality of word lines. The memory cells are disposed in strings coupled to one of a plurality of bit lines and are configured to retain a threshold voltage corresponding to one of a plurality of data states. A control means is configured to read each of the memory cells in a read operation. For each one of the memory cells, the control means is also configured to offset at least one of a bit line settling time and a kick voltage during the read operation based on a probability of at least one neighboring one of the plurality of bit lines being coupled to the memory cells retaining the threshold voltage corresponding to a different one of the plurality of data states than the one of the memory cells.
    Type: Application
    Filed: March 29, 2022
    Publication date: October 5, 2023
    Applicant: SanDisk Technologies LLC
    Inventors: Yanjie Wang, Guirong Liang, Xiaoyu Che, Yi Song
  • Publication number: 20230317170
    Abstract: The memory device includes a plurality of memory cells that are arranged in a plurality of word lines. A controller is provided, and the controller is configured to program the memory cells to respective threshold voltages in a programming operation. The controller is configured to, in the programming operation, apply a first voltage to a control gate of a selected word line of the plurality of word lines. The controller is also configured to continuously ramp a voltage applied to the control gate of the selected word line from the first voltage to a programming voltage over a first duration. The controller is further configured to hold the voltage applied to the control gate of the selected word line at the programming voltage over a second duration that is less than the first duration.
    Type: Application
    Filed: April 5, 2022
    Publication date: October 5, 2023
    Applicant: SanDisk Technologies LLC
    Inventors: Xiaoyu Che, Yanjie Wang, Guirong Liang
  • Patent number: 11688469
    Abstract: To help reduce program disturbs in non-selected NAND strings of a non-volatile memory, a sub-block based boosting scheme in introduced. For a three dimensional NAND memory structure, in which the memory cells above a joint region form an upper sub-block and memory cells below the joint region form a lower sub-block, dummy word lines in the joint region act as select gates to allow boosting at the sub-block level when the lower block is being programmed in a reverse order.
    Type: Grant
    Filed: August 11, 2021
    Date of Patent: June 27, 2023
    Assignee: SanDisk Technologies LLC
    Inventors: Dengtao Zhao, Gerrit Jan Hemink, Xiang Yang, Ken Oowada, Guirong Liang
  • Patent number: 11636897
    Abstract: An apparatus includes a plurality of solid-state storage elements, a plurality of control lines coupled to the plurality of solid-state storage elements, and control circuitry in communication with the plurality of control lines. The control circuitry is configured to during a first phase of a control line pre-charging stage, charge one or more unselected control lines of the plurality of control lines using a regulated charging current for a period of time based at least in part on a predicted parasitic capacitance associated with the programming state of the control lines, and during a second phase of the control line pre-charging stage, charge the one or more unselected bit lines to an inhibit voltage level using an unregulated charging current.
    Type: Grant
    Filed: March 3, 2021
    Date of Patent: April 25, 2023
    Inventors: Yanjie Wang, Henry Chin, Guirong Liang, Jianzhi Wu
  • Patent number: 11605437
    Abstract: The non-volatile memory includes a control circuitry that is communicatively coupled to an array of memory cells that are arranged in a plurality of word lines. The control circuitry is configured to program the memory cells of the plurality of word lines to a plurality of data states in a multi-pass programming operation. A later programming pass of the multi-pass programming operation includes a plurality of programming loops with incrementally increasing programming pulses. For at least one data state, the later programming pass includes maintaining a count of the programming loops of the later programming pass. The later programming pass also includes inhibiting or slowing programming of the memory cells being programmed to one of the data states during a predetermined program count verify (PCV) programming loop and a PCV?1 programming loop and skipping a verify operation for all programming loops prior to a PCV+1 programming loop.
    Type: Grant
    Filed: June 25, 2021
    Date of Patent: March 14, 2023
    Assignee: SanDisk Technologies LLC
    Inventors: Yanjie Wang, Guirong Liang, Shota Murai, Xiaoyu Che
  • Publication number: 20230050955
    Abstract: To help reduce program disturbs in non-selected NAND strings of a non-volatile memory, a sub-block based boosting scheme in introduced. For a three dimensional NAND memory structure, in which the memory cells above a joint region form an upper sub-block and memory cells below the joint region form a lower sub-block, dummy word lines in the joint region act as select gates to allow boosting at the sub-block level when the lower block is being programmed in a reverse order.
    Type: Application
    Filed: August 11, 2021
    Publication date: February 16, 2023
    Applicant: SanDisk Technologies LLC
    Inventors: Dengtao Zhao, Gerrit Jan Hemink, Xiang Yang, Ken Oowada, Guirong Liang
  • Publication number: 20220415417
    Abstract: The non-volatile memory includes a control circuitry that is communicatively coupled to an array of memory cells that are arranged in a plurality of word lines. The control circuitry is configured to program the memory cells of the plurality of word lines to a plurality of data states in a multi-pass programming operation. A later programming pass of the multi-pass programming operation includes a plurality of programming loops with incrementally increasing programming pulses. For at least one data state, the later programming pass includes maintaining a count of the programming loops of the later programming pass. The later programming pass also includes inhibiting or slowing programming of the memory cells being programmed to one of the data states during a predetermined program count verify (PCV) programming loop and a PCV?1 programming loop and skipping a verify operation for all programming loops prior to a PCV+1 programming loop.
    Type: Application
    Filed: June 25, 2021
    Publication date: December 29, 2022
    Applicant: SanDisk Technologies LLC
    Inventors: Yanjie Wang, Guirong Liang, Shota Murai, Xiaoyu Che
  • Publication number: 20220284964
    Abstract: An apparatus includes a plurality of solid-state storage elements, a plurality of control lines coupled to the plurality of solid-state storage elements, and control circuitry in communication with the plurality of control lines. The control circuitry is configured to during a first phase of a control line pre-charging stage, charge one or more unselected control lines of the plurality of control lines using a regulated charging current for a period of time based at least in part on a predicted parasitic capacitance associated with the programming state of the control lines, and during a second phase of the control line pre-charging stage, charge the one or more unselected bit lines to an inhibit voltage level using an unregulated charging current.
    Type: Application
    Filed: March 3, 2021
    Publication date: September 8, 2022
    Applicant: SanDisk Technologies LLC
    Inventors: Yanjie Wang, Henry Chin, Guirong Liang, Jianzhi Wu
  • Patent number: 11139031
    Abstract: A storage device is disclosed herein. The storage device comprises a block including a plurality of memory cells and a circuit coupled to the plurality of memory cells of the block. The circuit is configured to determine data states for a first set of memory cells of a neighboring word line of the set of word lines, determine a bit line voltage bias and a sense time for a memory cell of a second set of memory cells of the selected word line based on a data state determined for a memory cell for each memory cell of the second set of memory cells, and perform a verify operation on the selected word line using the bit line voltage bias and the sense time determined for each memory cell of the second set of memory cells.
    Type: Grant
    Filed: June 17, 2020
    Date of Patent: October 5, 2021
    Assignee: SanDisk Technologies LLC
    Inventors: Han-Ping Chen, Guirong Liang, Henry Chin
  • Patent number: 9805809
    Abstract: Apparatuses, systems, methods, and computer program products are disclosed for state-dependent read compensation. A set of non-volatile storage cells comprising a plurality of word lines. A controller is configured to perform a read operation on one or more word lines adjacent to a target word line. A controller is configured to determine a read setting for application to a target word line based on a result of a read operation on one or more word lines adjacent to the target word line. A controller is configured to perform a read operation on a target word line using a determined read setting.
    Type: Grant
    Filed: August 31, 2016
    Date of Patent: October 31, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Zhenming Zhou, Guirong Liang, Gerrit Jan Hemink, Dana Lee, Chandu Gorla, Sarath Puthenthermadam, Deepanshu Dutta
  • Patent number: 9785357
    Abstract: Systems and methods for sampling data at a non-volatile memory system are disclosed. In one implementation, a controller of a non-volatile memory system that is coupled with a host device acquires a read level voltage of a first word line of a memory block of a non-volatile memory of the non-volatile memory system. The controller accesses one or more lookup tables to determine an offset voltage for a second word line of the memory block based on a program/erase count and a read/disturb count associated with the memory block; applies the read level voltage and the offset voltage to the second word line to sample data stored at the memory block; and determines whether the data sampled from the memory block contains errors.
    Type: Grant
    Filed: October 20, 2015
    Date of Patent: October 10, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Deepak Raghu, Chris Aviala, Harish Singidi, Guirong Liang, Anne Pao-Ling Koh, Dana Lee, Gautam Dusija
  • Patent number: 9672934
    Abstract: Systems and methods are disclosed for programming data in a non-volatile memory array are disclosed. A data storage device includes a non-volatile memory array including a plurality of non-volatile memory cells and a controller configured to receive a signal indicating a temperature of at least a portion of the data storage device. The controller determines a first offset program verify level associated with a first programming level based at least in part on the temperature and programs a first set of the memory cells of the non-volatile memory array using the first offset program verify level.
    Type: Grant
    Filed: February 25, 2016
    Date of Patent: June 6, 2017
    Assignee: Western Digital Technologies, Inc.
    Inventors: Guirong Liang, Haibo Li, Dengtao Zhao, Yongke Sun, Kroum S. Stoev
  • Publication number: 20170109040
    Abstract: Systems and methods for sampling data at a non-volatile memory system are disclosed. In one implementation, a controller of a non-volatile memory system that is coupled with a host device acquires a read level voltage of a first word line of a memory block of a non-volatile memory of the non-volatile memory system. The controller accesses one or more lookup tables to determine an offset voltage for a second word line of the memory block based on a program/erase count and a read/disturb count associated with the memory block; applies the read level voltage and the offset voltage to the second word line to sample data stored at the memory block; and determines whether the data sampled from the memory block contains errors.
    Type: Application
    Filed: October 20, 2015
    Publication date: April 20, 2017
    Applicant: SANDISK TECHNOLOGIES INC.
    Inventors: Deepak Raghu, Chris Aviala, Harish Singidi, Guirong Liang, Anne Pao-LIng Koh, Dana Lee, Gautam Dusija
  • Patent number: 9583206
    Abstract: A method includes, responsive to a power-up event at a data storage device that includes a memory, reading a flag stored at the data storage device and determining that the flag has a first value indicating that a reflow operation has not previously been detected at the memory. The method also includes, in response to determining that the flag has the first value, performing reflow detection at the memory. The method further includes, in response to the reflow detection indicating that the reflow operation has occurred, setting the flag to a second value.
    Type: Grant
    Filed: October 2, 2014
    Date of Patent: February 28, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Ting Luo, Jianmin Huang, Changyuan Chen, Guirong Liang
  • Patent number: 9563504
    Abstract: Systems and methods for performing partial block erase operations on a subset of word lines within a memory array prior to performing data refreshing or open-block programming are described. In some cases, data stored in memory cells connected to a word line with a fail bit count above an error threshold (e.g., more than two bit errors per page or more than three bit errors per word line) may be refreshed by performing a read operation on the memory cells, generating corrected data for the memory cells, performing a partial block erase operation on one or more word lines including the word line, and then writing the corrected data into the memory cells. The one or more word lines may include the word line with the fail bit count above the error threshold and an adjacent word line that is adjacent to the word line.
    Type: Grant
    Filed: September 24, 2015
    Date of Patent: February 7, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Guirong Liang, Zhenming Zhou, Masaaki Higashitani