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: 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: 10430262
    Abstract: Apparatus having an array of memory cells include a controller configured to read a particular memory cell of a last written page of memory cells of a block of memory cells of the array of memory cells, determine whether a threshold voltage of the particular memory cell is less than a particular voltage level, and mark the last written page of memory cells as affected by power loss during a programming operation of the last written page of memory cells when the threshold voltage of the particular memory cell is determined to be higher than the particular voltage level.
    Type: Grant
    Filed: November 2, 2018
    Date of Patent: October 1, 2019
    Assignee: Micron Technology, Inc.
    Inventors: Michael G. Miller, Ashutosh Malshe, Violante Moschiano, Peter Feeley, Gary F. Besinga, Sampath K. Ratnam, Walter Di-Francesco, Renato C. Padilla, Jr., Yun Li, Kishore Kumar Muchherla
  • 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
  • Publication number: 20190295660
    Abstract: Devices and techniques for read voltage calibration of a flash-based storage system based on host IO operations are disclosed. In an example, a memory device includes a NAND memory array having groups of multiple blocks of memory cells, and a memory controller to optimize voltage calibration for reads of the memory array. In an example, the optimization technique includes monitoring read operations occurring to a respective block, identifying a condition to trigger a read level calibration based on the read operations, and performing the read level calibration for the respective block or a memory component that includes the respective block. In a further example, the calibration is performed based on a threshold voltage to read the respective block, which may be considered when the threshold voltage to read the respective block is evaluated within a sampling operation performed by the read level calibration.
    Type: Application
    Filed: June 10, 2019
    Publication date: September 26, 2019
    Inventors: Ashutosh Malshe, Kishore Kumar Muchherla, Harish Reddy Singidi, Peter Sean Feeley, Sampath Ratnam, Kulachet Tanpairoj, Ting Luo
  • Publication number: 20190278653
    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: Application
    Filed: March 7, 2018
    Publication date: September 12, 2019
    Inventors: Renato Padilla, JR., Gary F. Besinga, Harish Singidi, Gianni Stephen Alsasua, Ashutosh Malshe, Kishore Kumar Muchherla, Vamsi Pavan Rayaprolu, Sampath Ratnam
  • Publication number: 20190278491
    Abstract: Data to store at a storage system is received. The storage system includes data blocks and the plurality of blocks that include a first region corresponding to a first storage density and a second region corresponding to a second storage density that is less dense than the first storage density. The data is stored at the first region of the plurality of data blocks that corresponds to the first storage density. A write attribute related to storing the data at the first region of the plurality of data blocks is determined. Thereupon, the write attribute related to storing the data at the first region is stored in the second region of the plurality of data blocks that corresponds to the second storage density.
    Type: Application
    Filed: March 6, 2018
    Publication date: September 12, 2019
    Inventors: Vamsi Pavan Rayaprolu, Sampath K. Ratnam, Kishore Kumar Muchherla, Harish R. Singidi, Ashutosh Malshe, Gianni S. Alsasua
  • Publication number: 20190272881
    Abstract: A memory device comprising a main memory and a controller operably connected to the main memory is provided. The main memory can comprise a plurality of memory addresses, each corresponding to a single one of a plurality of word lines. Each memory address can be included in a tracked subset of the plurality of memory addresses. Each tracked subset can include memory addresses corresponding to more than one of the plurality of word lines. The controller is configured to track a number of read operations for each tracked subset, and to scan, in response to the number of read operations for a first tracked subset exceeding a first threshold value, a portion of data corresponding to each word line of the first tracked subset to determine an error count corresponding to each word line of the first tracked subset.
    Type: Application
    Filed: May 18, 2019
    Publication date: September 5, 2019
    Inventors: Renato C. Padilla, Jung Sheng Hoei, Michael G. Miller, Roland J. Awusie, Sampath K. Ratnam, Kishore Kumar Muchherla, Gary F. Besinga, Ashutosh Malshe, Harish R. Singidi
  • Patent number: 10403378
    Abstract: A temperature associated with the memory component is determined. A frequency to perform an operation on a memory cell associated with the memory component is determined based on the temperature associated with the memory component. The operation is performed on the memory cell at the determined frequency to transition the memory cell from a state associated with an increased error rate for data stored at the memory cell to another state associated with a decreased error rate for the data stored at the memory cell.
    Type: Grant
    Filed: May 29, 2018
    Date of Patent: September 3, 2019
    Assignee: MICRON TECHNOLOGY, INC.
    Inventors: Sampath K. Ratnam, Vamsi Pavan Rayaprolu, Mustafa N. Kaynak, Peter Feeley, Kishore Kumar Muchherla, Renato C. Padilla, Shane Nowell
  • Publication number: 20190250843
    Abstract: At least one data of a set of data stored at a memory cell of a memory component is determined to be associated with an unsuccessful error correction operation. A determination is made as to whether a programming operation associated with the set of data stored at the memory cell has completed. The at least one data of the set of data stored at the memory cell that is associated with the unsuccessful error correction operation is recovered in response to determining that the programming operation has completed. Another memory cell of the memory component is identified in response to recovering the at least one data of the set of data stored at the memory cell that is associated with the unsuccessful error correction operation. The set of data including the recovered at least one data is provided to the other memory cell of the memory component.
    Type: Application
    Filed: August 10, 2018
    Publication date: August 15, 2019
    Inventors: Sampath K. Ratnam, Vamsi Pavan Rayaprolu, Mustafa N. Kaynak, Sivagnanam Parthasarathy, Kishore Kumar Muchherla, Shane Nowell, Peter Feeley, Qisong Lin
  • Publication number: 20190252028
    Abstract: A temperature associated with the memory component is determined. A frequency to perform an operation on a memory cell associated with the memory component is determined based on the temperature associated with the memory component. The operation is performed on the memory cell at the determined frequency to transition the memory cell from a state associated with an increased error rate for data stored at the memory cell to another state associated with a decreased error rate for the data stored at the memory cell.
    Type: Application
    Filed: May 29, 2018
    Publication date: August 15, 2019
    Inventors: Sampath K. Ratnam, Vamsi Pavan Rayaprolu, Mustafa N. Kaynak, Peter Feeley, Kishore Kumar Muchherla, Renato C. Padilla, Shane Nowell
  • Publication number: 20190243704
    Abstract: A number of operations that have been performed on one or more memory cells that are proximate to a particular memory cell of the memory component can be identified. A determination as to 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 can be made based on the identified number of operations. 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 25, 2018
    Publication date: August 8, 2019
    Inventors: Kishore Kumar Muchherla, Vamsi Pavan Rayaprolu, Peter Feeley, Sampath K. Ratnam, Sivagnanam Parthasarathy, Qisong Lin, Shane Nowell, Mustafa N. Kaynak
  • Publication number: 20190237146
    Abstract: Devices and techniques for initiating and controlling preemptive idle time read scans in a flash based storage system are disclosed. In an example, a memory device includes a NAND memory array and a memory controller to schedule and initiate read scans among multiple locations of the memory array, with such read scans being preemptively triggered during an idle (background) state of the memory device, thus reducing host latency during read and write operations in an active (foreground) state of the memory device. In an example, the optimization technique includes scheduling a read scan operation, monitoring an active or idle state of host IO operations, and preemptively initiating the read scan operation when entering an idle state, before the read scan operation is scheduled to occur. In further examples, the read scan may preemptively occur based on time-based scheduling, frequency-based conditions, or event-driven conditions triggering the read scan.
    Type: Application
    Filed: April 11, 2019
    Publication date: August 1, 2019
    Inventors: Ashutosh Malshe, Harish Reddy Singidi, Kishore Kumar Muchherla, Michael G. Miller, Sampath Ratman, Xu Zhang, Jie Zhou
  • Patent number: 10366763
    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: October 31, 2017
    Date of Patent: July 30, 2019
    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: 10365854
    Abstract: A variety of applications can include apparatus and/or methods that include tracking data temperatures of logical block addresses for a memory device by operating multiple accumulators by one or more data temperature analyzers to count host writes to ranges of logical block addresses. Data temperature for data written by a host is a measure of how frequently data at a logical block address is overwritten. In various embodiments, tracking can include staggering the start of counting by each of the multiple accumulators to provide subsequent binning of logical block addresses bands into temperature zones, which can achieve better data segregation. Data having a logical block address received from a host can be routed to a block associated with a temperature zone based on the binning provided by the staggered operation of the multiple accumulators by one or more data temperature analyzers. Additional apparatus, systems, and methods are disclosed.
    Type: Grant
    Filed: March 19, 2018
    Date of Patent: July 30, 2019
    Assignee: Micron Technology, Inc.
    Inventors: Kishore Kumar Muchherla, Peter Sean Feeley, Ashutosh Malshe, Sampath Ratnam, Harish Singidi, Vamsi Pavan Rayaprolu
  • Publication number: 20190227870
    Abstract: User data that is to be stored at a memory system can be received. System data associated with the memory system can be identified and the user data and the system data can be stored at the memory system based on an error control operation. A subset of the system data can be identified and the subset of the system data can be stored at the memory system based on another error control operation.
    Type: Application
    Filed: July 6, 2018
    Publication date: July 25, 2019
    Inventors: Vamsi Rayaprolu, Sivagnanam Parthasarathy, Sampath K. Ratnam, Peter Feeley, Kishore Kumar Muchherla
  • Patent number: 10354732
    Abstract: Devices and techniques for NAND temperature data management are disclosed herein. A command to write data to a NAND component in the NAND device is received at a NAND controller of the NAND device. A temperature corresponding to the NAND component is obtained in response to receiving the command. The command is then executed to write data to the NAND component and to write a representation of the temperature. The data is written to a user portion and the representation of the temperature is written to a management portion that is accessible only to the controller and segregated from the user portion.
    Type: Grant
    Filed: August 30, 2017
    Date of Patent: July 16, 2019
    Assignee: Micron Technology, Inc.
    Inventors: Kishore Kumar Muchherla, Sampath Ratnam, Preston Thomson, Harish Singidi, Jung Sheng Hoei, Peter Sean Feeley, Jianmin Huang
  • Patent number: 10347344
    Abstract: Devices and techniques for read voltage calibration of a flash-based storage system based on host IO operations are disclosed. In an example, a memory device includes a NAND memory array having groups of multiple blocks of memory cells, and a memory controller to optimize voltage calibration for reads of the memory array. In an example, the optimization technique includes monitoring read operations occurring to a respective block, identifying a condition to trigger a read level calibration based on the read operations, and performing the read level calibration for the respective block or a memory component that includes the respective block. In a further example, the calibration is performed based on a threshold voltage to read the respective block, which may be considered when the threshold voltage to read the respective block is evaluated within a sampling operation performed by the read level calibration.
    Type: Grant
    Filed: August 29, 2017
    Date of Patent: July 9, 2019
    Assignee: Micron Technology, Inc.
    Inventors: Ashutosh Malshe, Kishore Kumar Muchherla, Harish Singidi, Peter Sean Feeley, Sampath Ratnam, Kulachet Tanpairoj, Ting Luo
  • Patent number: 10340016
    Abstract: A memory device comprising a main memory and a controller operably connected to the main memory. The main memory can comprise a plurality of memory addresses, each corresponding to a single one of a plurality of word lines. Each memory address can be included in a tracked subset of the plurality of memory addresses. Each tracked subset can include memory addresses corresponding to more than one of the plurality of word lines. The controller is configured to track a number of read operations for each tracked subset, and to scan, in response to the number of read operations for a first tracked subset exceeding a first threshold value, a portion of data corresponding to each word line of the first tracked subset to determine an error count corresponding to each word line of the first tracked subset.
    Type: Grant
    Filed: June 26, 2017
    Date of Patent: July 2, 2019
    Assignee: Micron Technology, Inc.
    Inventors: Renato C. Padilla, Jung Sheng Hoei, Michael G. Miller, Roland J. Awusie, Sampath K. Ratnam, Kishore Kumar Muchherla, Gary F. Besinga, Ashutosh Malshe, Harish R. Singidi
  • Patent number: 10303535
    Abstract: Apparatus include controllers configured to iteratively program a group of memory cells to respective desired data states; determine whether a power loss to the apparatus is indicated while iteratively programming the group of memory cells; and if a power loss to the apparatus is indicated, to change the desired data state of the particular memory cell before continuing with the programming. Apparatus further include controllers configured to read a particular memory cell of a last written page of memory cells, determine whether a threshold voltage of the particular memory cell is less than a particular voltage level, and to mark the last written page of memory cells as affected by power loss during a programming operation of the last written page of memory cells when the threshold voltage of the particular memory cell is determined to be higher than the particular voltage level.
    Type: Grant
    Filed: March 5, 2018
    Date of Patent: May 28, 2019
    Assignee: Micron Technology, Inc.
    Inventors: Michael G. Miller, Ashutosh Malshe, Violante Moschiano, Peter Feeley, Gary F. Besinga, Sampath K. Ratnam, Walter Di-Francesco, Renato C. Padilla, Jr., Yun Li, Kishore Kumar Muchherla
  • Patent number: 10283205
    Abstract: Devices and techniques for initiating and controlling preemptive idle time read scans in a flash based storage system are disclosed. In an example, a memory device includes a NAND memory array and a memory controller to schedule and initiate read scans among multiple locations of the memory array, with such read scans being preemptively triggered during an idle (background) state of the memory device, thus reducing host latency during read and write operations in an active (foreground) state of the memory device. In an example, the optimization technique includes scheduling a read scan operation, monitoring an active or idle state of host IO operations, and preemptively initiating the read scan operation when entering an idle state, before the read scan operation is scheduled to occur. In further examples, the read scan may preemptively occur based on time-based scheduling, frequency-based conditions, or event-driven conditions triggering the read scan.
    Type: Grant
    Filed: September 30, 2017
    Date of Patent: May 7, 2019
    Assignee: Micron Technology, Inc.
    Inventors: Ashutosh Malshe, Harish Singidi, Kishore Kumar Muchherla, Michael G. Miller, Sampath Ratnam, John Zhang, Jie Zhou