Patents by Inventor Harish Singidi

Harish Singidi 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).

  • Patent number: 11854611
    Abstract: A multiphase programming scheme for programming a plurality of memory cells of a data storage system includes a first programming phase in which a first set of voltage distributions of the plurality of memory cells is programmed by applying a first plurality of program pulses to word lines of the plurality of memory cells, and a second programming phase in which a second set of voltage distributions is programmed by applying a second plurality of program pulses to the word lines of the plurality of memory cells. The second programming phase includes maintaining a margin of separation between two adjacent voltage distributions of the second set of voltage distributions after each of the second plurality of program pulses. This scheme achieves better margin using an aggressive quick pass approach, which helps with data recovery in case of power loss events.
    Type: Grant
    Filed: May 21, 2021
    Date of Patent: December 26, 2023
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Harish Singidi, Amiya Banerjee, Shantanu Gupta
  • Patent number: 11727996
    Abstract: A storage device can reorganize a sequentially performed calibration task and delegate various steps of the task to multiple memory planes. By utilizing a characteristic that provides for similar memory device responses across multiple planes, the calibration task processed on one memory plane can be applied to another memory plane within the device. In this way, partial calibration data may be generated across a plurality of memory planes, and subsequently pooled together to generate a unified calibration data that can be utilized on each of the plurality of planes to do a full calibrated read on memory devices, thus reducing the amount of time needed to perform a calibrated read. Reduced times for calibrated reads allows for increased resolution of threshold valley scans, increased lifespan of the storage device, improved read times, and also provides for data write methods to use less memory during intermediate multi-pass programming steps.
    Type: Grant
    Filed: October 6, 2022
    Date of Patent: August 15, 2023
    Assignee: Western Digital Technologies, Inc.
    Inventors: Harish Singidi, Amiya Banerjee, Shantanu Gupta
  • Publication number: 20230129097
    Abstract: Memory devices, or memory systems, described herein may include a controller (e.g., SSD controller) and a NAND memory device for storing inflight data. When the power loss event occurs, a memory system maintains (i.e., not un-select) the existing memory block being programmed at the time of power loss. The existing program operation at the event of power loss can be suspended by controller. The inflight data can be re-sent by controller directly to NAND latches, when power loss event was detected. The memory system can select a next, immediate available erased page and begin one-pulse programming to store the inflight data, without ramping down the program pump and program pulse, which was in use before the power loss event. The existing programming voltage is used to store/program the inflight data via single pulse programming. When power is restored, the inflight data is moved/programmed to another block for good data reliability.
    Type: Application
    Filed: October 25, 2021
    Publication date: April 27, 2023
    Applicant: SanDisk Technologies LLC
    Inventors: Shantanu Gupta, Amiya Banerjee, Harish Singidi
  • Publication number: 20230023725
    Abstract: A storage device can reorganize a sequentially performed calibration task and delegate various steps of the task to multiple memory planes. By utilizing a characteristic that provides for similar memory device responses across multiple planes, the calibration task processed on one memory plane can be applied to another memory plane within the device. In this way, partial calibration data may be generated across a plurality of memory planes, and subsequently pooled together to generate a unified calibration data that can be utilized on each of the plurality of planes to do a full calibrated read on memory devices, thus reducing the amount of time needed to perform a calibrated read. Reduced times for calibrated reads allows for increased resolution of threshold valley scans, increased lifespan of the storage device, improved read times, and also provides for data write methods to use less memory during intermediate multi-pass programming steps.
    Type: Application
    Filed: October 6, 2022
    Publication date: January 26, 2023
    Inventors: Harish Singidi, Amiya Banerjee, Shantanu Gupta
  • Patent number: 11527300
    Abstract: A method, apparatus, and system for level dependent error correction code protection in multi-level non-volatile memory. A write command to write data to a non-volatile memory array may be received. At least one multi-level page of multi-level storage cells may be determined for the write data. A coding rate for the write data of the at least one multi-level page may be determined based on an attribute of the at least one multi-level page. An ECC codeword may be generated that satisfies the coding rate and includes the write data. The ECC codeword may then be stored on the at least one multi-level page.
    Type: Grant
    Filed: March 26, 2021
    Date of Patent: December 13, 2022
    Assignee: Western Digital Technologies, Inc.
    Inventors: Nian Yang, Sahil Sharma, Harish Singidi
  • Publication number: 20220375513
    Abstract: A multiphase programming scheme for programming a plurality of memory cells of a data storage system includes a first programming phase in which a first set of voltage distributions of the plurality of memory cells is programmed by applying a first plurality of program pulses to word lines of the plurality of memory cells, and a second programming phase in which a second set of voltage distributions is programmed by applying a second plurality of program pulses to the word lines of the plurality of memory cells. The second programming phase includes maintaining a margin of separation between two adjacent voltage distributions of the second set of voltage distributions after each of the second plurality of program pulses. This scheme achieves better margin using an aggressive quick pass approach, which helps with data recovery in case of power loss events.
    Type: Application
    Filed: May 21, 2021
    Publication date: November 24, 2022
    Applicant: SANDISK TECHNOLOGIES LLC
    Inventors: Harish Singidi, Amiya Banerjee, Shantanu Gupta
  • Patent number: 11468953
    Abstract: A storage device can reorganize a sequentially performed calibration task and delegate various steps of the task to multiple memory planes. By utilizing a characteristic that provides for similar memory device responses across multiple planes, the calibration task processed on one memory plane can be applied to another memory plane within the device. In this way, partial calibration data may be generated across a plurality of memory planes, and subsequently pooled together to generate a unified calibration data that can be utilized on each of the plurality of planes to do a full calibrated read on memory devices, thus reducing the amount of time needed to perform a calibrated read. Reduced times for calibrated reads allows for increased resolution of threshold valley scans, increased lifespan of the storage device, improved read times, and also provides for data write methods to use less memory during intermediate multi-pass programming steps.
    Type: Grant
    Filed: March 10, 2021
    Date of Patent: October 11, 2022
    Assignee: Western Digital Technologies, Inc.
    Inventors: Harish Singidi, Amiya Banerjee, Shantanu Gupta
  • Patent number: 11456037
    Abstract: Disclosed in some examples, are methods, systems, and machine readable mediums which compensate for read-disturb effects by shifting the read voltages used to read the value in a NAND cell based upon a read counter. For example, the NAND memory device may have a read counter that corresponds to a group of NAND cells (e.g., a page, a block, a superblock). Anytime a NAND cell in the group is read, the read counter may be incremented. The read voltage, Vread, may be adjusted based on the read counter to account for the read disturb voltage.
    Type: Grant
    Filed: May 12, 2021
    Date of Patent: September 27, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Harish Singidi, Kishore Kumar Muchherla, Gianni Stephen Alsasua, Ashutosh Malshe, Sampath Ratnam, Gary F. Besinga, Michael G. Miller
  • Publication number: 20220293191
    Abstract: A storage device can reorganize a sequentially performed calibration task and delegate various steps of the task to multiple memory planes. By utilizing a characteristic that provides for similar memory device responses across multiple planes, the calibration task processed on one memory plane can be applied to another memory plane within the device. In this way, partial calibration data may be generated across a plurality of memory planes, and subsequently pooled together to generate a unified calibration data that can be utilized on each of the plurality of planes to do a full calibrated read on memory devices, thus reducing the amount of time needed to perform a calibrated read. Reduced times for calibrated reads allows for increased resolution of threshold valley scans, increased lifespan of the storage device, improved read times, and also provides for data write methods to use less memory during intermediate multi-pass programming steps.
    Type: Application
    Filed: March 10, 2021
    Publication date: September 15, 2022
    Inventors: Harish Singidi, Amiya Banerjee, Shantanu Gupta
  • Publication number: 20220068423
    Abstract: A method, apparatus, and system for level dependent error correction code protection in multi-level non-volatile memory. A write command to write data to a non-volatile memory array may be received. At least one multi-level page of multi-level storage cells may be determined for the write data. A coding rate for the write data of the at least one multi-level page may be determined based on an attribute of the at least one multi-level page. An ECC codeword may be generated that satisfies the coding rate and includes the write data. The ECC codeword may then be stored on the at least one multi-level page.
    Type: Application
    Filed: March 26, 2021
    Publication date: March 3, 2022
    Applicant: Western Digital Technologies, Inc.
    Inventors: Nian YANG, Sahil SHARMA, Harish SINGIDI
  • Patent number: 11126495
    Abstract: A system configured to determine that a trigger condition has occurred that is related to an operation performed on a memory device of the system. Responsive to determining that the trigger condition has occurred, reordering error handling mechanisms of an error handling sequence based upon an error handling mechanism performance metric. Each error handling mechanism specifies operations to be performed to recover an error in the operation on the memory device.
    Type: Grant
    Filed: March 7, 2018
    Date of Patent: September 21, 2021
    Assignee: Micron Technology, Inc.
    Inventors: Renato Padilla, Jr., Gary F. Besinga, Harish Singidi, Gianni Stephen Alsasua, Ashutosh Malshe, Kishore Kumar Muchherla, Vamsi Pavan Rayaprolu, Sampath Ratnam
  • Publication number: 20210264991
    Abstract: Disclosed in some examples, are methods, systems, and machine readable mediums which compensate for read-disturb effects by shifting the read voltages used to read the value in a NAND cell based upon a read counter. For example, the NAND memory device may have a read counter that corresponds to a group of NAND cells (e.g., a page, a block, a superblock). Anytime a NAND cell in the group is read, the read counter may be incremented. The read voltage, Vread, may be adjusted based on the read counter to account for the read disturb voltage.
    Type: Application
    Filed: May 12, 2021
    Publication date: August 26, 2021
    Inventors: Harish Singidi, Kishore Kumar Muchherla, Gianni Stephen Alsasua, Ashutosh Malshe, Sampath Ratnam, Gary F. Besinga, Michael G. Miller
  • Patent number: 11024394
    Abstract: A memory sub-system can be determined to be operating within a target operating characteristic based on a threshold success rate associated with error control operations using a particular parameter. Upon determining that the memory sub-system is operating within the target operating characteristic, a sticky read mode is entered by performing subsequent read operations using the particular parameter. It is determined that additional error control operations are triggered for at least a first threshold number of read operations using the particular parameter during the sticky read mode. Upon determining that the additional error control operations are triggered for at least the first threshold number of read operations using the particular parameter during the sticky read mode, the sticky read mode is exited by performing further read operations using a default parameter associated with the memory sub-system.
    Type: Grant
    Filed: April 9, 2020
    Date of Patent: June 1, 2021
    Assignee: MICRON TECHNOLOGY, INC.
    Inventors: Harish Singidi, Kishore Muchherla, Ashutosh Malshe, Vamsi Rayaprolu, Sampath Ratnam, Renato Padilla, Jr., Michael Miller
  • Patent number: 10755793
    Abstract: NAND memory devices are described that utilize higher read-margin cell types to provide a more granular read disturb indicator without utilizing dummy cells. For example, a NAND architecture may have some cells that are configured as SLC or MLC cells. SLC or MLC cells have more read disturb margin—that is these cells can withstand more read disturb current leakage into the cell before a bit error occurs than TLC or QLC cells. These higher margin cells may serve as the read disturb indicator for a group of cells that have a comparatively lower read disturb margin. Since there are more pages of these higher margin cells than there are pages of dummy cells, these indicators may serve a smaller group of pages than the dummy pages. This reduces the time needed to complete a read disturb scan as fewer pages need to be scanned.
    Type: Grant
    Filed: October 31, 2017
    Date of Patent: August 25, 2020
    Assignee: Micron Technology, Inc.
    Inventors: Harish Singidi, Scott Stoller, Jung Sheng Hoei, Ashutosh Malshe, Gianni Stephen Alsasua, Kishore Kumar Muchherla
  • Publication number: 20200234775
    Abstract: A memory sub-system can be determined to be operating within a target operating characteristic based on a threshold success rate associated with error control operations using a particular parameter. Upon determining that the memory sub-system is operating within the target operating characteristic, a sticky read mode is entered by performing subsequent read operations using the particular parameter. It is determined that additional error control operations are triggered for at least a first threshold number of read operations using the particular parameter during the sticky read mode. Upon determining that the additional error control operations are triggered for at least the first threshold number of read operations using the particular parameter during the sticky read mode, the sticky read mode is exited by performing further read operations using a default parameter associated with the memory sub-system.
    Type: Application
    Filed: April 9, 2020
    Publication date: July 23, 2020
    Inventors: Harish Singidi, Kishore Muchherla, Ashutosh Malshe, Vamsi Rayaprolu, Sampath Ratnam, Renato Padilla, JR., Michael Miller
  • Patent number: 10658047
    Abstract: A memory sub-system can be determined to be operating within a target operating characteristic based on a threshold success rate associated with error control operations using a particular parameter. Upon determining that the memory sub-system is operating within the target operating characteristic, a sticky read mode is entered by performing subsequent read operations using the particular parameter. It is determined that additional error control operations are triggered for at least a first threshold number of read operations using the particular parameter during the sticky read mode. Upon determining that the additional error control operations are triggered for at least the first threshold number of read operations using the particular parameter during the sticky read mode, the sticky read mode is exited by performing further read operations using a default parameter associated with the memory sub-system.
    Type: Grant
    Filed: October 31, 2018
    Date of Patent: May 19, 2020
    Assignee: Micron Technology, Inc.
    Inventors: Harish Singidi, Kishore Muchherla, Ashutosh Malshe, Vamsi Rayaprolu, Sampath Ratnam, Renato Padilla, Jr., Michael Miller
  • Publication number: 20200135279
    Abstract: A memory sub-system can be determined to be operating within a target operating characteristic based on a threshold success rate associated with error control operations using a particular parameter. Upon determining that the memory sub-system is operating within the target operating characteristic, a sticky read mode is entered by performing subsequent read operations using the particular parameter. It is determined that additional error control operations are triggered for at least a first threshold number of read operations using the particular parameter during the sticky read mode. Upon determining that the additional error control operations are triggered for at least the first threshold number of read operations using the particular parameter during the sticky read mode, the sticky read mode is exited by performing further read operations using a default parameter associated with the memory sub-system.
    Type: Application
    Filed: October 31, 2018
    Publication date: April 30, 2020
    Inventors: Harish Singidi, Kishore Muchherla, Ashutosh Malshe, Vamsi Rayaprolu, Sampath Ratnam, Renato Padilla, JR., Michael Miller
  • Patent number: 10522229
    Abstract: Disclosed in some examples are systems, methods, memory devices, and machine readable mediums for a fast secure data destruction for NAND memory devices that renders data in a memory cell unreadable. Instead of going through all the erase phases, the memory device may remove sensitive data by performing only the pre-programming phase of the erase process. Thus, the NAND doesn't perform the second and third phases of the erase process. This is much faster and results in data that cannot be reconstructed. In some examples, because the erase pulse is not actually applied and because this is simply a programming operation, data may be rendered unreadable at a per-page level rather than a per-block level as in traditional erases.
    Type: Grant
    Filed: August 30, 2017
    Date of Patent: December 31, 2019
    Assignee: Micron Technology, Inc.
    Inventors: Ting Luo, Kulachet Tanpairoj, Harish Singidi, Jianmin Huang, Preston Thomson, Sebastien Andre Jean
  • Patent number: 10446197
    Abstract: A variety of applications can include apparatus and/or methods of operating the apparatus that include a memory device having read levels that can be calibrated. A calibration controller implemented with the memory device can trigger a read level calibration based on inputs from one or more trackers monitoring parameters associated with the memory device and a determination of an occurrence of at least one event from a set of events related to the monitored parameters. The monitored parameters can include parameters related to a selected time interval and measurements of read, erase, or write operations of the memory device. Additional apparatus, systems, and methods are disclosed.
    Type: Grant
    Filed: August 31, 2017
    Date of Patent: October 15, 2019
    Assignee: Micron Technology, Inc.
    Inventors: Kishore Kumar Muchherla, Ashutosh Malshe, Harish Singidi, Gianni Stephen Alsasua, Gary F. Besinga, Sampath Ratnam, Peter Sean Feeley
  • Patent number: 10430116
    Abstract: Devices and techniques for correcting for power loss in NAND memory devices are disclosed herein. The NAND memory devices may comprise a number of physical pages. For example, a memory controller may detect a power loss indicator at the NAND flash memory. The memory controller may identify a last-written physical page and determine whether the last-written physical page comprises more than a threshold number of low-read-margin cells. If the last-written physical page comprises more than the threshold number of low-read-margin cells, the memory controller may provide a programming voltage to at least the low-read-margin cells.
    Type: Grant
    Filed: August 31, 2017
    Date of Patent: October 1, 2019
    Assignee: Micron Technology, Inc.
    Inventors: Michael G. Miller, Kishore Kumar Muchherla, Harish Singidi, Sampath Ratnam, Renato C. Padilla, Jr., Gary F. Besinga, Peter Sean Feeley