Patents by Inventor Kishore Kumar Muchherla

Kishore Kumar Muchherla 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: 11436078
    Abstract: Disclosed in some examples are techniques for handling parity data of a non-volatile memory device with limited cache memory. In certain examples, user data can be programmed into the non-volatile memory of the non-volatile memory device in data stripes, and parity information can be calculated for each individual data stripe within a limited capacity cache of the non-volatile memory device. The individual parity information can be swapped between a swap block of the non-volatile memory and the limited capacity cache as additional data stripes are programmed.
    Type: Grant
    Filed: April 12, 2021
    Date of Patent: September 6, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Harish Reddy Singidi, Xiangang Luo, Jianmin Huang, Kishore Kumar Muchherla, Ashutosh Malshe, Vamsi Pavan Rayaprolu, Sampath Ratnam
  • Publication number: 20220277798
    Abstract: Systems and methods are disclosed including a memory device and a processing device operatively coupled to the memory device. The processing device can perform operations including receiving a read command to perform a read operation on a block of the memory device, determining a pass-through voltage for the block based on a metadata table, and performing the read operation by applying a read reference voltage to a selected wordline of the block and applying the pass-through voltage to a plurality of unselected wordlines of the block.
    Type: Application
    Filed: March 1, 2021
    Publication date: September 1, 2022
    Inventors: Kishore Kumar Muchherla, Mustafa N. Kaynak, Sampath K. Ratnam, Peter Feeley, Sivagnanam Parthasarathy
  • Publication number: 20220277787
    Abstract: Devices and techniques for temperature informed memory refresh are described herein. A temperature counter can be updated in response to a memory device write performed under an extreme temperature. Here, the write is performed on a memory device element in the memory device. The memory device element can be sorted above other memory device elements in the memory device based on the temperature counter. Once sorted to the top of these memory device elements, a refresh can be performed the memory device element.
    Type: Application
    Filed: May 16, 2022
    Publication date: September 1, 2022
    Inventors: Gianni Stephen Alsasua, Harish Reddy Singidi, Kishore Kumar Muchherla, Sampath Ratnam, Ashutosh Malshe, Vamsi Pavan Rayaprolu, Renato Padilla, JR.
  • Patent number: 11430526
    Abstract: In a coarse programming, the threshold voltage of the memory cell is programmed to a first level representative of N?1 bit values data according to a first mapping between combinations of values of N?1 possible bits and threshold levels. A group identification is representative of whether the first level is an odd or even numbered level in the first mapping. For a fine programming, the memory cell is read, based on the group identification, to obtain the N?1 bit values; and at least one additional bit is received to join the N?1 bit values to form at least N bit values. The threshold voltage of the memory cell is then finely programmed to a second level representative of the at least N bit values according to a second mapping between combinations of values of the at least N possible bits and threshold levels.
    Type: Grant
    Filed: December 18, 2020
    Date of Patent: August 30, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Phong Sy Nguyen, James Fitzpatrick, Kishore Kumar Muchherla
  • Publication number: 20220269559
    Abstract: A variety of applications can include use of parity groups in a memory system with the parity groups arranged for data protection of the memory system. Each parity group can be structured with multiple data pages in which to write data and a parity page in which to write parity data generated from the data written in the multiple data pages. Each data page of a parity group can have storage capacity to include metadata of data written to the data page. Information can be added to the metadata of a data page with the information identifying an asynchronous power loss status of data pages that precede the data page in an order of writing data to the data pages of the parity group. The information can be used in re-construction of data in the parity group following an uncorrectable error correction code error in writing to the parity group.
    Type: Application
    Filed: May 11, 2022
    Publication date: August 25, 2022
    Inventors: Harish Reddy Singidi, Kishore Kumar Muchherla, Xiangang Luo, Vamsi Pavan Rayaprolu, Ashutosh Malshe
  • Patent number: 11417405
    Abstract: A variety of applications can include systems and/or methods of optimizing results from scanning a memory device, where the memory device has stacked multiple reliability specifications. Information about a block of multiple blocks of a memory device can be logged, where the information is associated with a combination of reliability specifications. A refresh of the block can be triggered based on exceeding a threshold condition for the combination of reliability specifications.
    Type: Grant
    Filed: January 5, 2021
    Date of Patent: August 16, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Ankit Vinod Vashi, Harish Reddy Singidi, Kishore Kumar Muchherla
  • Patent number: 11410734
    Abstract: A processing device of a memory sub-system is configured to detect a power on event associated with the memory device; scan one or more blocks of a plurality of blocks of the memory device to determine a corresponding time after program (TAP) associated with each block of the one or more blocks; estimate, based on the corresponding TAP of the each block of the one or more blocks, a duration of a power off state preceding the power on event; and update voltage bin assignments of the plurality of blocks associated with the memory device based on the duration of the power off state.
    Type: Grant
    Filed: March 31, 2021
    Date of Patent: August 9, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Kishore Kumar Muchherla, Sampath K Ratnam, Shane Nowell, Sivagnanam Parthasarathy, Mustafa N Kaynak, Karl D Schuh, Peter Feeley, Jiangang Wu
  • Publication number: 20220246214
    Abstract: A memory system to store multiple bits of data in a memory cell. A memory device coarsely programs a threshold voltage of the memory cell to a first level representative of a combination of bit values according to a mapping between bit value combinations and threshold levels. The threshold levels are partitioned into groups, each containing a subset of the threshold levels and having associated read voltages separating threshold levels in the subset. A group identification of a first group, among the groups, containing the first level is determined for the memory cell. The memory device applies read voltages of different groups, interleaved in an increasing order in a sequence, to read the memory cell when a read voltage applied is associated with the first group. The data bits read back from the memory cell are used to finely program the threshold voltage of the memory cell.
    Type: Application
    Filed: April 20, 2022
    Publication date: August 4, 2022
    Inventors: Phong Sy Nguyen, James Fitzpatrick, Kishore Kumar Muchherla
  • Publication number: 20220246207
    Abstract: A method can include receiving a request to read data from a memory cell of a memory device coupled with the processing device, determining a voltage distribution parameter value associated with the memory cell, determining a set of read levels associated with the voltage distribution parameter value, wherein each read level in the determined set of read levels corresponds to a respective voltage distribution of the memory cell, and reading, using the determined set of read levels, data from the memory cell. The voltage distribution parameter value can be determined by identifying a particular voltage distribution of the memory cell by sampling the memory cell at a plurality of voltage levels, and determining the voltage distribution parameter value based on the particular voltage distribution. The voltage distribution parameter value can be a voltage value that is included in the particular voltage distribution.
    Type: Application
    Filed: February 1, 2021
    Publication date: August 4, 2022
    Inventors: Shane Nowell, Steven Michael Kientz, Michael Sheperek, Mustafa N Kaynak, Kishore Kumar Muchherla, Larry J Koudele, Bruce A Liikanen
  • Patent number: 11403228
    Abstract: Various embodiments described herein provide for a page program sequence for a block of a memory device, such as a negative-and (NAND)-type memory device, where all the wordlines are programmed with respect to a given set of page types (e.g., LP pages) prior to wordlines are programmed with respect to a next set of page types (e.g., UP and XP pages).
    Type: Grant
    Filed: August 20, 2020
    Date of Patent: August 2, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Kulachet Tanpairoj, Jianmin Huang, Tomoko Ogura Iwasaki, Kishore Kumar Muchherla, Peter Sean Feeley
  • Publication number: 20220237094
    Abstract: A memory system includes a memory device and a processing device, operatively coupled to the memory device. The processing device performs operations comprising: identifying an operating temperature of the memory device; determining that the operating temperature satisfies a temperature condition; modifying a scan frequency parameter for performing a scan operation on representative blocks of a set of blocks in the memory device; and performing the scan operation at a frequency identified by the scan frequency parameter.
    Type: Application
    Filed: January 25, 2021
    Publication date: July 28, 2022
    Inventors: Michael Sheperek, Steven Michael Kientz, Shane Nowell, Mustafa N. Kaynak, Kishore Kumar Muchherla, Larry J. Koudele
  • Publication number: 20220236871
    Abstract: A processing device access a command to program data to a page in a block of a memory device. The processing device determines whether the page is a last remaining open page in the block. The processing device accesses a list that indicates enablement of a function to apply read level offsets to one or more open blocks in the memory device. The processing device determines the list includes an entry that matches to the block. The entry indicates enablement of the function to apply read level offsets to the block. The processing device disables the function based on determining the page is a last remaining open page in the block. The processing device adds the command to a prioritized queue of commands. The memory device executes commands from the prioritized queue in an order based on a priority level assigned to each command.
    Type: Application
    Filed: January 27, 2021
    Publication date: July 28, 2022
    Inventors: Jiangang Wu, Jung Sheng Hoei, Qisong Lin, Kishore Kumar Muchherla
  • Publication number: 20220229564
    Abstract: A processing device in a memory system assigns a memory page to a sensitivity tier of a plurality of sensitivity tiers. The processing device determines respective scan intervals for the plurality of sensitivity tiers, wherein the respective scan intervals are based on at least one characteristic of a memory device, the at least one characteristic comprising memory cell margins of the memory device. The processing device scans a subset of a plurality of memory pages, wherein the subset comprises a number of memory pages from each sensitivity tier identified according to the respective scan intervals.
    Type: Application
    Filed: April 7, 2022
    Publication date: July 21, 2022
    Inventors: Kishore Kumar Muchherla, Gary F. Besinga, Cory M. Steinmetz, Pushpa Seetamraju, Jiangang Wu, Sampath K. Ratnam, Peter Feeley
  • Publication number: 20220229554
    Abstract: A block family associated with a memory device is initialized. An initial value of a power cycle count associated with the memory device is stored. Responsive to programming a block residing in the memory device, the block is associated with the block family. Responsive to determining that a current value of the power cycle count exceeds the initial value of the power cycle count, the block family is closed. Responsive to determining that a time period that has elapsed since initializing the block family exceeds a threshold period, the block family is closed.
    Type: Application
    Filed: January 20, 2021
    Publication date: July 21, 2022
    Inventors: Kishore Kumar Muchherla, Mustafa N. Kaynak, Jiangang Wu, Sampath K. Ratnam, Sivagnanam Parthasarathy, Peter Feeley, Karl D. Schuh
  • Patent number: 11393541
    Abstract: A determination that a programming operation has been performed on a memory cell can be made. An amount of time that has elapsed since the programming operation has been performed on the memory cell can be identified. A determination as to whether the amount of time that has elapsed satisfies a threshold time condition can be made. In response to determining that the amount of time that has elapsed satisfies the threshold time condition an operation can be performed on the memory cell to change or maintain a voltage condition of the memory cell.
    Type: Grant
    Filed: December 21, 2020
    Date of Patent: July 19, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Vamsi Pavan Rayaprolu, Kishore Kumar Muchherla, Peter Feeley, Sampath K. Ratnam, Sivagnanam Parthasarathy, Qisong Lin, Shane Nowell, Mustafa N. Kaynak
  • Publication number: 20220221993
    Abstract: Systems and methods are disclosed, including maintaining an error recovery data structure for a set of codewords (CWs) in a storage system, the error recovery data structure storing indications that specific CWs are correctable or not correctable by specific error handing (EH) steps of a set of multiple EH steps, and determine an order of EH steps for the storage system based on the error recovery data structure. Maintaining the error recovery data structure can include determining if each CW of the set of CWs is correctable by a specific EH step, storing indications of CWs determined correctable by the specific EH step in the error recovery data structure, and, in response to determining that one or more CW in the set of CWs are not indicated as correctable in the error recovery data structure, incrementing the specific EH step.
    Type: Application
    Filed: March 30, 2022
    Publication date: July 14, 2022
    Inventors: Xiangang Luo, Harish Reddy Singidi, Ting Luo, Kishore Kumar Muchherla
  • Patent number: 11379122
    Abstract: A set of memory cells in a data block of a memory component is sampled. A distribution statistic is generated for the data block based on a reliability statistic for each of the set of sampled memory cells. A determination is made based on the distribution statistic of whether the read disturb stress is uniformly or non-uniformly distributed across the data block. In response to a determination that the read disturb stress is non-uniformly distributed across the data block, a first subset of the data block is relocated to another data block of the memory component. The first subset of the data block is associated with a higher concentration of read disturb stress than other subsets of the data block.
    Type: Grant
    Filed: February 18, 2021
    Date of Patent: July 5, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Ashutosh Malshe, Kishore Kumar Muchherla, Vamsi Pavan Rayaprolu, Harish R. Singidi
  • Patent number: 11379355
    Abstract: A total estimated occupancy value of a first data on a first data block of a plurality of data blocks is determined. To determine the total estimated occupancy value of the first data block, a total block power-on-time (POT) value of the first data block is determined. Then, a scaling factor is applied to the total block POT value to determine the total estimated occupancy value of the first data block. Whether the total estimated occupancy value of the first data block satisfies a threshold criterion is determined. Responsive to determining that the total estimated occupancy value of the first data block satisfies the threshold criterion, data stored at the first data block is relocated to a second data block of the plurality of data blocks.
    Type: Grant
    Filed: October 30, 2018
    Date of Patent: July 5, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Kishore Kumar Muchherla, Renato C. Padilla, Sampath K. Ratnam, Saeed Sharifi Tehrani, Peter Feeley, Kevin R. Brandt
  • Publication number: 20220199184
    Abstract: A system includes a memory array with sub-blocks, each sub-block having groups of memory cells. A processing device, operatively coupled with the memory array, is to perform operations including performing, after a wordline is programmed through the sub-blocks, scanning of the wordline. The scanning includes selecting, to sample first data of the wordline, a first group of the groups of memory cells of a first sub-block of the sub-blocks; selecting, to sample second data of the wordline, a second group of the groups of memory cells of a second sub-block of the sub-blocks; concurrently reading the first data from the first group and the second data from the second group of the groups of memory cells; and performing an error check of the wordline using the first data and the second data.
    Type: Application
    Filed: December 18, 2020
    Publication date: June 23, 2022
    Inventors: Kishore Kumar Muchherla, Violante Moschiano, Sead Zildzic, Junwyn A. Lacsao, Paing Z. Htet
  • Publication number: 20220199165
    Abstract: Control logic in a memory device identifies a first plurality of groups of programming distributions, wherein each group comprises a subset of programming distributions associated with a portion of a memory array of the memory device configured as quad-level (QLC) memory. During a first pass of a multi-pass programming operation, the control logic coarsely programs memory cells in the portion configured as QLC memory to initial values representing a second plurality of pages of host data and stores, in a portion of the memory array of the memory device configured as single-level cell (SLC) memory, an indicator of the first plurality of groups of programming distributions with which each of the coarsely programmed memory cells is associated.
    Type: Application
    Filed: December 18, 2020
    Publication date: June 23, 2022
    Inventors: Phong Sy Nguyen, James Fitzpatrick, Kishore Kumar Muchherla