Patents by Inventor Sivagnanam Parthasarathy

Sivagnanam Parthasarathy 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: 20230017591
    Abstract: An initial value of a power cycle count associated with the memory device is identified. The power cycle count is incremented responsive to detecting a powering up of the memory device. Responsive to programming a block residing in the memory device, the block is associated with a current block family associated with the memory device. A currently value of the power cycle count is determined. Responsive to determining that a difference between the initial value of the power cycle count and the current value of the power cycle count satisfies a predefined condition, the current block family is closed.
    Type: Application
    Filed: September 21, 2022
    Publication date: January 19, 2023
    Inventors: Kishore Kumar Muchherla, Mustafa N. Kaynak, Jiangang Wu, Sampath K. Ratnam, Sivagnanam Parthasarathy, Peter Feeley, Karl D. Schuh
  • Publication number: 20230012648
    Abstract: A memory system configured to dynamically adjust the amount of redundant information stored in memory cells of a wordline on an integrated circuit die based on a bit error rate. For example, in response to a determination that a bit error rate of the wordline is above a threshold, the memory system can store first data items as independent first codewords of an error correction code technique into a first portion of the memory cells of the wordline, generate second data items as redundant information from the first codewords, and store the second data items in a second portion of the memory cells of the wordline. If the bit error rate is below the threshold, third data items can be stored as independent second codewords of the same length as the first codewords in the memory cells of the wordline.
    Type: Application
    Filed: June 15, 2022
    Publication date: January 19, 2023
    Inventors: James Fitzpatrick, Phong Sy Nguyen, Dung Viet Nguyen, Sivagnanam Parthasarathy
  • Publication number: 20230012978
    Abstract: A system includes a memory component to, upon completion of second pass programming in response to a multi-pass programming command, write a plurality of flag bits within a group of memory cells programmed by the multi-pass programming command. The system also includes a processing device, operatively coupled to the memory component. The processing device is to detect an error in attempting to read a top page of the group of memory cells, determine a number of first values within the plurality of flag bits, and in response to the number of first values not satisfying a threshold criterion, report, to a host computing device, an uncorrectable data error due to the top page of the group of memory cells being incompletely programmed.
    Type: Application
    Filed: September 16, 2022
    Publication date: January 19, 2023
    Inventors: Qisong LIN, Vamsi Pavan RAYAPROLU, Jiangang WU, Sampath K. RATNAM, Sivagnanam PARTHASARATHY, Shao Chun SHI
  • Patent number: 11557361
    Abstract: A memory device to determine a voltage optimized to read a group of memory cells by reading the group of memory cells at a plurality of test voltages, computing bit counts at the test voltages respectively, and computing count differences in the bit counts for pairs of adjacent voltages in the test voltages. When a smallest one in the count differences is found at a side of a distribution of the count differences according to voltage, the memory device is configured to determine a location of an optimized read voltage, based on a ratio between a first count difference and a second count difference, where the first count difference is the smallest in the count differences, and the second count difference is closest in voltage to the first count difference.
    Type: Grant
    Filed: April 23, 2021
    Date of Patent: January 17, 2023
    Assignee: Micron Technology, Inc.
    Inventors: Patrick Robert Khayat, James Fitzpatrick, Abdelhakim S. Alhussien, Sivagnanam Parthasarathy
  • Patent number: 11556417
    Abstract: A memory device to use added known data as part of data written to memory cells with redundant data generated according to an Error Correction Code (ECC). The code rate of the ECC may limit its capability to recover from excessive errors in the stored data. To reduce the errors, the added data retrieved from the memory cells can be corrected without using the ECC. Subsequently, remaining errors can be corrected via the ECC. Optionally, the added data can be configured to be the same as the data represented by an erased state of a subset of the memory cells such that when the subset is used to store the added data, the subset remains in the erased state to reduce wearing. Different subsets can be used to store added data for different write operations to distribute the benefit of reduced wearing.
    Type: Grant
    Filed: December 22, 2021
    Date of Patent: January 17, 2023
    Assignee: Micron Technology, Inc.
    Inventors: Sivagnanam Parthasarathy, Kishore Kumar Muchherla, Akira Goda, Mustafa N. Kaynak
  • Publication number: 20230005557
    Abstract: A memory device to program a group of memory cells to store multiple bits per memory cell. Each bit per memory cell in the group from a page. After determining a plurality of read voltages of the group of memory cells, the memory device can read the multiple pages of the group using the plurality of read voltages. For each respective page in the multiple pages, the memory device can determine a count of first memory cells in the respective page that have threshold voltages higher than a highest read voltage, among the plurality of read voltages, used to read the respective page. The count of the first memory cells can be compared with a predetermined range of a fraction of memory cells in the respective page to evaluate the plurality of read voltages (e.g., whether any of the read voltages is in a wrong voltage range).
    Type: Application
    Filed: September 7, 2022
    Publication date: January 5, 2023
    Inventors: Sivagnanam Parthasarathy, James Fitzpatrick, Patrick Robert Khayat, AbdelHakim S. Alhussien
  • Publication number: 20230004328
    Abstract: A memory sub-system configured to: measure a plurality of sets of signal and noise characteristics of a group of memory cells in a memory device; determine a plurality of optimized read voltages of the group of memory cells from the plurality of sets of signal and noise characteristics respectively; generate features from the plurality of sets of signal and noise characteristics, including at least one compound feature generated from the plurality of sets of signal and noise characteristics; generate, using the features, a classification of a bit error rate of data retrievable from the group of memory cells; and control an operation to read the group of memory cells based on the classification.
    Type: Application
    Filed: September 7, 2022
    Publication date: January 5, 2023
    Inventors: Sivagnanam Parthasarathy, James Fitzpatrick, Patrick Robert Khayat, AbdelHakim S. Alhussien
  • Publication number: 20220416815
    Abstract: Methods, systems, and apparatuses include receiving a codeword stored in a memory device. The codeword is error corrected for a first number of iterations. The error correction includes traversing the codeword according to a first order. The codeword is error corrected for a second number of the iterations. The error correction of the codeword during a second iteration from the second number of iterations includes traversing the codeword according to a second order that is different from the first order.
    Type: Application
    Filed: August 30, 2022
    Publication date: December 29, 2022
    Inventors: Mustafa N. KAYNAK, Sivagnanam PARTHASARATHY
  • Patent number: 11532373
    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: Grant
    Filed: March 18, 2021
    Date of Patent: December 20, 2022
    Assignee: MICRON TECHNOLOGY, INC.
    Inventors: Kishore Kumar Muchherla, Shane Nowell, Mustafa N. Kaynak, Sampath K. Ratnam, Peter Feeley, Sivagnanam Parthasarathy, Devin M. Batutis, Xiangang Luo
  • Publication number: 20220392547
    Abstract: A voltage shift for memory cells of a block family at a memory device is measured. The block family is associated with a first voltage offset. An adjusted amount of voltage shift is determined for the memory cells based on the measured voltage shift and a temporary voltage shift offset associated with a difference between a current temperature and a prior temperature for the memory device. The block family is associated with a second voltage offset in view of the adjusted voltage shift.
    Type: Application
    Filed: August 18, 2022
    Publication date: December 8, 2022
    Inventors: Kishore Kumar Muchherla, Karl Schuh, Mustafa N. Kaynak, Xiangang Luo, Shane Nowell, Devin Batutis, Sivagnanam Parthasarathy, Sampath Ratnam, Jiangang Wu, Peter Feeley
  • Publication number: 20220392554
    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 performing a read operation on a block of the memory device by applying a read reference voltage to a selected wordline of the block and applying a pass-through voltage having a first value to a plurality of unselected wordlines of the block; detecting a read error in response to performing the read operation; and setting the pass-through voltage to a second value, wherein the second value is greater than the first value.
    Type: Application
    Filed: August 17, 2022
    Publication date: December 8, 2022
    Inventors: Kishore Kumar Muchherla, Mustafa N. Kaynak, Sampath K. Ratnam, Peter Feeley, Sivagnanam Parthasarathy
  • Publication number: 20220383955
    Abstract: A processing device of a memory sub-system is configured to detect a power on event that is associated with a memory device and indicates that power has been restored to the memory device; estimate a duration of a power off state preceding the power on event associated with the memory device; and update voltage bin assignments of a plurality of blocks associated with the memory device based on the duration of the power off state.
    Type: Application
    Filed: August 8, 2022
    Publication date: December 1, 2022
    Inventors: Kishore Kumar MUCHHERLA, Sampath K. RATNAM, Shane NOWELL, Sivagnanam PARTHASARATHY, Mustafa N. KAYNAK, Karl D. SCHUH, Peter FEELEY, Jiangang WU
  • Patent number: 11514989
    Abstract: A memory device to manage the assignment of offset voltages for read operations, and to adjust read voltages using the offset voltages. The offset voltages are dynamically adjusted by a controller during operation of the memory device in response to read errors. In one approach, a first bin of offset voltages is assigned to a first region of a storage media. The first offset voltages are used to adjust read voltages for reading a page of first memory cells in the first region. The controller determines that at least one error has occurred in reading the page. In response to determining the error, the controller determines second offset voltages that can be used to read the first memory cell without causing a read error. Based on the second offset voltages, the controller identifies third offset voltages for assigning to the first region. The third offset voltages are used for adjusting read voltages for subsequent reads of pages in the first region.
    Type: Grant
    Filed: September 4, 2020
    Date of Patent: November 29, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Mustafa N. Kaynak, Sivagnanam Parthasarathy, Patrick Robert Khayat
  • Patent number: 11500564
    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: Grant
    Filed: January 20, 2021
    Date of Patent: November 15, 2022
    Assignee: MICRON TECHNOLOGY, INC.
    Inventors: Kishore Kumar Muchherla, Mustafa N. Kaynak, Jiangang Wu, Sampath K. Ratnam, Sivagnanam Parthasarathy, Peter Feeley, Karl D. Schuh
  • Publication number: 20220350700
    Abstract: Methods, systems, and apparatus for error correction with syndrome computation in a memory device are described. A first syndrome for first encoded data is generated in a memory device. The first syndrome and the first encoded data are transmitted to a controller that is coupled with the memory device. A second syndrome for first and second encoded data is generated. The first encoded data and the second encoded data are interrelated according to an error correction code. The second syndrome is transmitted to the controller without the second encoded data and the controller is to decode the first encoded data based on at least one of the first syndrome, the second syndrome, or a combination thereof.
    Type: Application
    Filed: April 30, 2021
    Publication date: November 3, 2022
    Inventors: Mustafa N. KAYNAK, Patrick R. KHAYAT, Sivagnanam PARTHASARATHY
  • Publication number: 20220351786
    Abstract: A determination that a first programming operation has been performed on a particular memory cell can be made. A determination can be made, based on one or more threshold criteria, whether the particular memory cell has transitioned from a state associated with a decreased error rate to another state associated with an increased error rate. In response to determining that the particular memory cell has transitioned from the state associated with the decreased error rate to the another state associated with the increased error rate, an operation can be performed on the particular memory cell to transition the particular memory cell from the another state associated with the increased error rate to the state associated with the decreased error rate.
    Type: Application
    Filed: July 19, 2022
    Publication date: November 3, 2022
    Inventors: Vamsi Pavan Rayaprolu, Kishore Kumar Muchherla, Peter Feeley, Sampath K. Ratnam, Sivagnanam Parthasarathy, Qisong Lin, Shane Nowell, Mustafa N. Kaynak
  • Publication number: 20220336023
    Abstract: A processing device of a memory sub-system is configured to identify a read level of a plurality of read levels associated with a voltage bin of a plurality of voltage bins of a memory device; assign a first threshold voltage offset to the read level of the voltage bin; assign a second threshold voltage offset to the read level of the voltage bin; perform, on block associated with the read level, a first operation of a first operation type using the first threshold voltage offset; and perform, on the blocks associated with the read level, a second operation of a second operation type using the second threshold voltage offset.
    Type: Application
    Filed: April 16, 2021
    Publication date: October 20, 2022
    Inventors: Kishore Kumar Muchherla, Mustafa N. Kaynak, Sampath K. Ratnam, Shane Nowell, Peter Feeley, Sivagnanam Parthasarathy
  • Publication number: 20220334752
    Abstract: A processing device of a memory sub-system is configured to identify a plurality of blocks assigned to a first voltage bin of a plurality of voltage bins of a memory device; identify a subset of the plurality of blocks having a time after program (TAP) within a predetermined threshold period of time from a second TAP associated with a transition boundary between the first voltage bin and a subsequent voltage bin of the plurality of voltage bins; determine a threshold voltage offset associated with the subset of blocks; and associate the threshold voltage offset with the subsequent voltage bin.
    Type: Application
    Filed: April 16, 2021
    Publication date: October 20, 2022
    Inventors: Kishore Kumar MUCHHERLA, Sampath K RATNAM, Shane NOWELL, Peter FEELEY, Sivagnanam Parthasarathy, Mustafa N Kaynak
  • Publication number: 20220334751
    Abstract: Exemplary methods, apparatuses, and systems include receiving a plurality of read operations directed to a portion of memory accessed by a memory channel. The plurality of read operations are divided into a current set of a sequence of read operations and one or more other sets of sequences of read operations. An aggressor read operation is selected from the current set. A supplemental memory location is selected independently of aggressors and victims in the current set of read operations. A first data integrity scan is performed on a victim of the aggressor read operation and a second data integrity scan is performed on the supplemental memory location.
    Type: Application
    Filed: April 15, 2021
    Publication date: October 20, 2022
    Inventors: Saeed Sharifi Tehrani, Ashutosh Malshe, Kishore Kumar Muchherla, Sivagnanam Parthasarathy, Vamsi Pavan Rayaprolu
  • Patent number: 11474748
    Abstract: A memory sub-system configured to: measure a plurality of sets of signal and noise characteristics of a group of memory cells in a memory device; determine a plurality of optimized read voltages of the group of memory cells from the plurality of sets of signal and noise characteristics respectively; generate features from the plurality of sets of signal and noise characteristics, including at least one compound feature generated from the plurality of sets of signal and noise characteristics; generate, using the features, a classification of a bit error rate of data retrievable from the group of memory cells; and control an operation to read the group of memory cells based on the classification.
    Type: Grant
    Filed: May 6, 2021
    Date of Patent: October 18, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Sivagnanam Parthasarathy, James Fitzpatrick, Patrick Robert Khayat, AbdelHakim S. Alhussien