Patents by Inventor Sampath Ratnam

Sampath Ratnam 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: 11335394
    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: Grant
    Filed: April 23, 2021
    Date of Patent: May 17, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Gianni Stephen Alsasua, Harish Reddy Singidi, Kishore Kumar Muchherla, Sampath Ratnam, Ashutosh Malshe, Vamsi Pavan Rayaprolu, Renato Padilla, Jr.
  • Patent number: 11269553
    Abstract: Systems and methods are disclosed, comprising a memory device comprising multiple groups of memory cells, the groups comprising a first group of memory cells and a second group of memory cells configured to store information at a same bit capacity per memory cell, and a processing device operably coupled to the memory device, the processing device configured to adjust a scan event threshold for one of the first or second groups of memory cells to a threshold less than a target scan event threshold for the first and second groups of memory cells to distribute scan events in time on the memory device.
    Type: Grant
    Filed: May 19, 2020
    Date of Patent: March 8, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Gianni Stephen Alsasua, Harish Reddy Singidi, Peter Sean Feeley, Ashutosh Malshe, Renato Padilla, Jr., Kishore Kumar Muchherla, Sampath Ratnam
  • Patent number: 11250918
    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 28, 2020
    Date of Patent: February 15, 2022
    Assignee: Micron Technology, Inc.
    Inventors: Ashutosh Malshe, Harish Reddy Singidi, Kishore Kumar Muchherla, Michael G. Miller, Sampath Ratnam, Xu Zhang, Jie Zhou
  • Publication number: 20210303394
    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: Application
    Filed: April 12, 2021
    Publication date: September 30, 2021
    Inventors: Harish Reddy Singidi, Xiangang Luo, Jianmin Huang, Kishore Kumar Muchherla, Ashutosh Malshe, Vamsi Pavan Rayaprolu, Sampath Ratnam
  • 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: 20210287748
    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: Application
    Filed: May 26, 2021
    Publication date: September 16, 2021
    Inventors: Kishore Kumar Muchherla, Sampath Ratnam, Preston Allen Thomson, Harish Reddy Singidi, Jung Sheng Hoei, Peter Sean Feeley, Jianmin Huang
  • 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
  • Publication number: 20210257031
    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: May 6, 2021
    Publication date: August 19, 2021
    Inventors: Ashutosh Malshe, Kishore Kumar Muchherla, Harish Reddy Singidi, Peter Sean Feeley, Sampath Ratnam, Kulachet Tanpairoj, Ting Luo
  • Publication number: 20210241823
    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: April 23, 2021
    Publication date: August 5, 2021
    Inventors: Gianni Stephen Alsasua, Harish Reddy Singidi, Kishore Kumar Muchherla, Sampath Ratnam, Ashutosh Malshe, Vamsi Pavan Rayaprolu, Renato Padilla, JR.
  • Publication number: 20210232342
    Abstract: Various examples are directed to systems and methods of managing a memory device. The memory device may receive a read request describing a logical address at the memory device. The memory device may obtain a table entry associated with the logical address. The table entry comprises a physical address corresponding to the logical address and a write temperature data indicating a write temperature for the logical address. The memory device may determine a corrected threshold voltage for reading the physical address based at least in part on the write temperature data and read the physical address using the corrected threshold voltage.
    Type: Application
    Filed: April 16, 2021
    Publication date: July 29, 2021
    Inventors: Gianni Stephen Alsasua, Karl D. Schuh, Ashutosh Malshe, Kishore Kumar Muchherla, Vamsi Pavan Rayaprolu, Sampath Ratnam, Harish Reddy Singidi, Renato Padilla, JR.
  • Patent number: 11068197
    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: July 2, 2019
    Date of Patent: July 20, 2021
    Assignee: Micron Technology, Inc.
    Inventors: Kishore Kumar Muchherla, Peter Sean Feeley, Ashutosh Malshe, Sampath Ratnam, Harish Reddy Singidi, Vamsi Pavan Rayaprolu
  • Patent number: 11056156
    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: January 22, 2020
    Date of Patent: July 6, 2021
    Assignee: Micron Technology, Inc.
    Inventors: Kishore Kumar Muchherla, Ashutosh Malshe, Harish Reddy Singidi, Gianni Stephen Alsasua, Gary F. Besinga, Sampath Ratnam, Peter Sean Feeley
  • Patent number: 11043278
    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: September 10, 2020
    Date of Patent: June 22, 2021
    Assignee: Micron Technology, Inc.
    Inventors: Ashutosh Malshe, Kishore Kumar Muchherla, Harish Reddy Singidi, Peter Sean Feeley, Sampath Ratnam, Kulachet Tanpairoj, Ting Luo
  • Patent number: 11037630
    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: April 23, 2020
    Date of Patent: June 15, 2021
    Assignee: Micron Technology, Inc.
    Inventors: Kishore Kumar Muchherla, Sampath Ratnam, Preston Allen Thomson, Harish Reddy Singidi, Jung Sheng Hoei, Peter Sean Feeley, Jianmin Huang
  • Patent number: 11031089
    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: July 2, 2020
    Date of Patent: June 8, 2021
    Assignee: Micron Technology, Inc.
    Inventors: Harish Reddy Singidi, Kishore Kumar Muchherla, Gianni Stephen Alsasua, Ashutosh Malshe, Sampath Ratnam, Gary F. Besinga, Michael G. Miller
  • Patent number: 11023177
    Abstract: A memory device may receive a read request describing a logical address at the memory device. The memory device may obtain a table entry associated with the logical address. The table entry comprises a physical address corresponding to the logical address and a write temperature data indicating a write temperature for the logical address. The memory device may determine a corrected threshold voltage for reading the physical address based at least in part on the write temperature data and read the physical address using the corrected threshold voltage.
    Type: Grant
    Filed: June 23, 2020
    Date of Patent: June 1, 2021
    Assignee: Micron Technology, Inc.
    Inventors: Gianni Stephen Alsasua, Karl D. Schuh, Ashutosh Malshe, Kishore Kumar Muchherla, Vamsi Pavan Rayaprolu, Sampath Ratnam, Harish Reddy Singidi, Renato Padilla, Jr.
  • 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: 10998034
    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: Grant
    Filed: September 10, 2020
    Date of Patent: May 4, 2021
    Assignee: Micron Technology, Inc.
    Inventors: Gianni Stephen Alsasua, Harish Reddy Singidi, Kishore Kumar Muchherla, Sampath Ratnam, Ashutosh Malshe, Vamsi Pavan Rayaprolu, Renato Padilla, Jr.
  • Patent number: 10977115
    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: October 12, 2018
    Date of Patent: April 13, 2021
    Assignee: Micron Technology, Inc.
    Inventors: Harish Reddy Singidi, Xiangang Luo, Jianmin Huang, Kishore Kumar Muchherla, Ashutosh Malshe, Vamsi Pavan Rayaprolu, Sampath Ratnam
  • Patent number: 10915395
    Abstract: Various examples are directed to systems and methods for reading a memory component. A processing device may receive an indication that a read operation at a physical address of the memory component failed. The processing device may execute a plurality of read retry operations at the physical address. The processing device may access a first syndrome weight describing a first error correction operation performed on a result of a first read retry operation of the plurality of read retry operations and a second syndrome weight describing a second error correction operation performed on a result of a second read retry operation of the plurality of read retry operations. The processing device may select a first threshold voltage associated with the first read retry operation based at least in part on the first syndrome weight and the second syndrome weight.
    Type: Grant
    Filed: November 16, 2018
    Date of Patent: February 9, 2021
    Assignee: Micron Technology, Inc.
    Inventors: Ting Luo, Kishore Kumar Muchherla, Harish Reddy Singidi, Xiangang Luo, Renato Padilla, Jr., Gary F. Besinga, Sampath Ratnam, Vamsi Pavan Rayaprolu