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).

  • Publication number: 20220319589
    Abstract: A method can include receiving a request to read data from a block of a memory device coupled with a processing device, determining, using a data structure mapping block identifiers to corresponding voltage distribution parameter values, a voltage distribution parameter value associated with the block of the memory device, determining a set of read levels associated with the voltage distribution parameter value, wherein each read level in the set of read levels corresponds to a respective voltage distribution of at least one memory cell comprised by the block, and reading, using the determined set of read levels, data from the block of the memory device.
    Type: Application
    Filed: March 30, 2021
    Publication date: October 6, 2022
    Inventors: Shane Nowell, Steven Michael Kientz, Michael Sheperek, Mustafa N Kaynak, Kishore Kumar Muchherla, Larry J Koudele, Bruce A Liikanen
  • Publication number: 20220319630
    Abstract: A method can include receiving a request to read data from a block of a memory device coupled with a processing device, determining, using a first data structure mapping block identifiers to corresponding block family identifiers, a block family associated with the block of the memory device, determining, using a second data structure mapping block family identifiers to corresponding voltage distribution parameter values, a voltage distribution parameter value associated with the block family, determining a set of read levels associated with the voltage distribution parameter value, wherein each read level in the set of read levels corresponds to a respective voltage distribution of at least one memory cell comprised by the block of the memory device, and reading, using the determined set of read levels, data from the block of the memory device.
    Type: Application
    Filed: March 30, 2021
    Publication date: October 6, 2022
    Inventors: Michael Sheperek, Kishore Kumar Muchherla, Shane Nowell, Mustafa N. Kaynak, Larry J. Koudele
  • Publication number: 20220317902
    Abstract: A processing device of a memory sub-system is configured to sort a plurality of blocks of the memory device; divide the sorted plurality of blocks into a plurality of block segments; scan a first block at a first boundary of a first block segment of the plurality of block segments; scan a second block at a second boundary of the first block segment; identify, based on a scanning result of the first block, a first voltage bin associated with the first block; identify, based on a second scanning result of the second block, a second voltage bin associated with the second block; and responsive to determining that the first voltage bin matches the second voltage bin, assign the first voltage bin to each block of a subset of the plurality of blocks assigned to the first block segment.
    Type: Application
    Filed: March 31, 2021
    Publication date: October 6, 2022
    Inventors: Kishore Kumar Muchherla, Mustafa N. Kaynak, Peter Feeley, Sampath K. Ratnam, Shane Nowell, Sivagnanam Parthasarathy, Karl D. Schuh, Jiangang Wu
  • Patent number: 11462265
    Abstract: A memory system to store multiple bits of data in a memory cell. After receiving the data bits, a memory device coarsely programs a threshold voltage of the memory cell to a first level representative of a combination of values of the data bits according to a mapping between combinations of values of bits and threshold levels. The threshold levels are partitioned into a plurality of groups, each containing a subset of the threshold levels. XOR (or XNOR) is used to combine the data bits into bits of a group identification of a first group, among the plurality of groups, that contains the first level. The memory device reads, using the group identification, the data bits back from the first memory cell to finely program the threshold voltage of the memory cell to represent the data bits.
    Type: Grant
    Filed: December 18, 2020
    Date of Patent: October 4, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Phong Sy Nguyen, James Fitzpatrick, Kishore Kumar Muchherla
  • Patent number: 11462280
    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: Grant
    Filed: March 1, 2021
    Date of Patent: October 4, 2022
    Assignee: MICRON TECHNOLOGY, INC.
    Inventors: Kishore Kumar Muchherla, Mustafa N. Kaynak, Sampath K. Ratnam, Peter Feeley, Sivagnanam Parthasarathy
  • Patent number: 11456038
    Abstract: A memory system to store multiple bits of data in a memory cell. After receiving the data bits, 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 combinations of bit values and threshold levels. The threshold levels are partitioned into a plurality of groups, each containing a subset of the threshold levels. A group identification of a first group, among the plurality of groups, containing the first level is determined for the memory cell. The memory device reads, using the group identification, a subset of the data bits back from the first memory cell, and combines the bits of the group identification and the subset to recover the entire set of data bits to finely program the threshold voltage of the memory cell to represent the data bits.
    Type: Grant
    Filed: December 18, 2020
    Date of Patent: September 27, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Phong Sy Nguyen, James Fitzpatrick, Kishore Kumar Muchherla
  • 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
  • Patent number: 11455109
    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: Grant
    Filed: January 27, 2021
    Date of Patent: September 27, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Jiangang Wu, Jung Sheng Hoei, Qisong Lin, Kishore Kumar Muchherla
  • Publication number: 20220301652
    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 detecting a read error with respect to data residing in a block of the memory device, wherein the block is associated with a voltage offset bin, determining an order of a plurality of error-handling operations to be performed to recovery data associated with the read error, wherein the order is specified in a metadata table and is based on the voltage offset bin associated with the block, and performing at least one error-handling operation of the plurality of error-handling operations in the order specified by the metadata table.
    Type: Application
    Filed: March 18, 2021
    Publication date: September 22, 2022
    Inventors: Kishore Kumar Muchherla, Shane Nowell, Mustafa N. Kaynak, Sampath K. Ratnam, Peter Feeley, Sivagnanam Parthasarathy, Devin M. Batutis, Xiangang Luo
  • Publication number: 20220300415
    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: Application
    Filed: June 7, 2022
    Publication date: September 22, 2022
    Inventors: Kishore Kumar MUCHHERLA, Renato C. PADILLA, Sampath K. RATNAM, Saeed SHARIFI TEHRANI, Peter FEELEY, Kevin R. BRANDT
  • Publication number: 20220300186
    Abstract: A current memory access voltage distribution is measured for a memory page of a block family associated with a first voltage bin of a plurality of voltage bins at a memory device. The first voltage bin is associated with a first voltage offset. A current value for a reference voltage is determined based on the current memory access voltage distribution measured for the memory page. An amount of voltage shift for the memory page is determined based on the current value for the reference voltage a prior value for the reference voltage. The prior value for the reference voltage is associated with a prior memory access voltage distribution for the memory page. In response to a determination that the amount of voltage shift satisfies a voltage shift criterion, the block family is associated with a second voltage bin of the plurality of voltage bins. The second voltage bin is associated with a second voltage offset.
    Type: Application
    Filed: March 16, 2021
    Publication date: September 22, 2022
    Inventors: Kishore Kumar Muchherla, Devin M. Batutis, Xiangang Luo, Mustafa N. Kaynak, Peter Feeley, Sivagnanam Parthasarathy, Sampath Ratnam, Shane Nowell
  • Patent number: 11450392
    Abstract: A processing device in a memory system maintains a counter to track a number of read operations performed on a data block of a memory device and determines that the number of read operations performed on the data block satisfies a first threshold criterion. The processing device further determines whether a number of scan operations performed on the data block satisfies a scan threshold criterion. Responsive to the number of scan operations performed on the data block satisfying the scan threshold criterion, the processing device performs a first data integrity scan to determine one or more first error rates for the data block, each of the one or more first error rates corresponding to a first set of wordlines of the data block, the first set comprising first alternating pairs of adjacent wordlines.
    Type: Grant
    Filed: December 17, 2019
    Date of Patent: September 20, 2022
    Assignee: MICRON TECHNOLOGY, INC.
    Inventors: Kishore Kumar Muchherla, Harish R. Singidi, Renato C. Padilla, Vamsi Pavan Rayaprolu, Ashutosh Malshe, Sampath K. Ratnam
  • Patent number: 11449271
    Abstract: An example memory sub-system comprises: a memory device; and a processing device, operatively coupled with the memory device. The processing device is configured to: receive a first host data item; store the first host data item in a first page of a first logical unit of a memory device, wherein the first page is associated with a fault tolerant stripe; receive a second host data item; store the second host data item in a second page of the first logical unit of the memory device, wherein the second page is associated with the fault tolerant stripe, and wherein the second page is separated from the first page by one or more wordlines including a dummy wordline storing no host data; and store, in a third page of a second logical unit of the memory device, redundancy metadata associated with the fault tolerant stripe.
    Type: Grant
    Filed: October 23, 2020
    Date of Patent: September 20, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Kishore Kumar Muchherla, Mark A. Helm, Giuseppina Puzzilli, Peter Feeley, Yifen Liu, Violante Moschiano, Akira Goda, Sampath K. Ratnam
  • Patent number: 11450391
    Abstract: A system includes a memory device and a processing device. The processing device performs, at a first frequency, a first scan of a page of a block family that measures a first data state metric and identifies a specific bin corresponding to a measured value for the first data state metric. Processing device updates a bin, to which the page is assigned, to match the specific bin. Processing device performs, at a second frequency higher than the first frequency, a second scan of the page to measure a second data state metric for read operations performed using a threshold voltage offset value from each of multiple bins. Processing device updates the bin, to which the page is assigned for the specified die, to match a second bin having the threshold voltage offset value that yields a lowest read bit error rate from the second scan.
    Type: Grant
    Filed: September 15, 2020
    Date of Patent: September 20, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Kishore Kumar Muchherla, Shane Nowell, Mustafa N. Kaynak, Karl D. Schuh, Jiangang Wu, Devin M. Batutis, Xiangang Luo
  • Publication number: 20220293208
    Abstract: A voltage calibration scan is initiated. A first value of a data state metric measured for a sample block of a memory device based on associated with a first bin of blocks designated as a current is received. The first value is designated as a minimum value. A second value of the data state metric for the sample block is measured based on a set of read voltage offsets associated with a second bin of blocks having an index value higher than the current bin. In response to determining that the second value exceeds the first value, the first bin is maintained as the current bin and the voltage calibration scan is stopped.
    Type: Application
    Filed: March 11, 2021
    Publication date: September 15, 2022
    Inventors: Kishore Kumar MUCHHERLA, Mustafa N. KAYNAK, Sivagnanam PARTHASARATHY, Xiangang LUO, Peter FEELEY, Devin M. BATUTIS, Jiangang WU, Sampath K RATNAM, Shane NOWELL, Karl D. Schuh
  • Publication number: 20220291849
    Abstract: Method includes identifying, while programming sets of pages to dice of memory device, multiple sets of pages experiencing a variation in temporal voltage shift satisfying a threshold criterion; partitioning a set of pages of the multiple sets of pages into a set of fixed-length partitions; storing, in a metadata table, a value to indicate a size of each fixed-length partition; receiving a read operation directed at a page of the set of pages; determining, based on a logical block address of the read operation and on the value that indicates the size of each fixed-length partition, a partition of the set of fixed-length partitions to which the read operation corresponds; and searching within the metadata table to determine a block family to which the partition is assigned, wherein the searching is based on a first value associated with the set of pages and a second value associated with the partition.
    Type: Application
    Filed: May 23, 2022
    Publication date: September 15, 2022
    Inventors: Kishore Kumar Muchherla, Karl D. Schuh, Jiangang Wu, Mastafa N. Kaynak, Devin M. Batutis, Xiangang Luo
  • Patent number: 11443830
    Abstract: A method can include receiving a request to read data from a block of a memory device coupled with a processing device, determining, using a first data structure mapping block identifiers to corresponding block family identifiers, a block family associated with the block of the memory device, determining, using a second data structure mapping block family identifiers to corresponding voltage distribution parameter values, a voltage distribution parameter value associated with the block family, determining a set of read levels associated with the voltage distribution parameter value, wherein each read level in the set of read levels corresponds to a respective voltage distribution of at least one memory cell comprised by the block of the memory device, and reading, using the determined set of read levels, data from the block of the memory device.
    Type: Grant
    Filed: March 30, 2021
    Date of Patent: September 13, 2022
    Assignee: MICRON TECHNOLOGY, INC.
    Inventors: Michael Sheperek, Kishore Kumar Muchherla, Shane Nowell, Mustafa N Kaynak, Larry J Koudele
  • Patent number: 11442641
    Abstract: An example memory sub-system includes a memory device and a processing device, operatively coupled to the memory device. The processing device is configured to create a first block family comprising a first set of blocks that have been programmed within at least one of a first specified time window or a first specified temperature window, wherein each block associated with the first block family is associated with a first set of read level offsets; create, a second block family comprising a second set of blocks that have been programmed within at least one of a second specified time window following the first specified time window or a second specified temperature window, wherein each block associated with the second block family is associated with a second set of read level offsets; and responsive to a determining that a threshold criterion is satisfied, combine the first and second block family.
    Type: Grant
    Filed: November 16, 2020
    Date of Patent: September 13, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Michael Sheperek, Kishore Kumar Muchherla, Shane Nowell
  • Patent number: 11436085
    Abstract: Write operations are performed to write data to user blocks of the memory device and to write, to a first set of purposed blocks, purposed data related to the first data written at the memory device. Whether the first set of purposed blocks satisfy a condition indicating an endurance state of the first set of purposed blocks is determined. Responsive to the first set of purposed blocks satisfies the condition, one or more blocks from a pool of storage area blocks of the memory device are allocated to a second set of purposed blocks.
    Type: Grant
    Filed: December 4, 2020
    Date of Patent: September 6, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Kishore Kumar Muchherla, Harish R. Singidi, Ashutosh Malshe, Vamsi Pavan Rayaprolu, Sampath K. Ratnam
  • Patent number: 11437108
    Abstract: A difference between a current temperature and a prior temperature of a memory device is determined. In response to a determination that the difference between the current temperature and the prior temperature of the memory device satisfies a temperature criterion, an amount of voltage shift is measured for a set of memory cells of a block family associated with a first voltage bin of a set of voltage bins at the memory device. The first voltage bin is associated with a first voltage offset. An adjusted amount of voltage shift is determined for the set of memory cells based on the determined amount of voltage shift and a temporary voltage shift offset associated with the difference between the current temperature and the prior temperature for the memory device. In response to a determination that the adjusted amount of voltage shift satisfies a voltage shift criterion, the block family is associated with a second voltage bin of the set of voltage bins.
    Type: Grant
    Filed: April 14, 2021
    Date of Patent: September 6, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Kishore Kumar Muchherla, Karl Schuh, Mustafa N Kaynak, Xiangang Luo, Shane Nowell, Devin Batutis, Sivagnanam Parthasarathy, Sampath Ratnam, Jiangang Wu, Peter Feeley