Patents by Inventor Dharmaraju Marenahally Krishna

Dharmaraju Marenahally Krishna 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: 11662941
    Abstract: Methods and systems for increasing reliability of a data storage device are disclosed. During fabrication runs of a non-volatile memory (NVM) die, such as a NAND, there may be a number of memory cells designated as erase cells. When one or more erase cells are physically adjacent to programmed memory cell, electrical effects of the erase cell may cause a bit to flip in the adjacent good memory cell. To mitigate this effect, an LDPC engine is used to generate additional parity bits for the erased bit/cells. When a host requests data from the NVM, the parity bits may be used to correct additional errors because of the erased state to programmed state bit flips.
    Type: Grant
    Filed: March 24, 2021
    Date of Patent: May 30, 2023
    Assignee: Western Digital Technologies, Inc.
    Inventors: Bhavadip Bipinbhai Solanki, Dharmaraju Marenahally Krishna
  • Publication number: 20220113893
    Abstract: Methods and systems for increasing reliability of a data storage device are disclosed. During fabrication runs of a non-volatile memory (NVM) die, such as a NAND, there may be a number of memory cells designated as erase cells. When one or more erase cells are physically adjacent to programmed memory cell, electrical effects of the erase cell may cause a bit to flip in the adjacent good memory cell. To mitigate this effect, an LDPC engine is used to generate additional parity bits for the erased bit/cells. When a host requests data from the NVM, the parity bits may be used to correct additional errors because of the erased state to programmed state bit flips.
    Type: Application
    Filed: March 24, 2021
    Publication date: April 14, 2022
    Inventors: Bhavadip Bipinbhai SOLANKI, Dharmaraju Marenahally KRISHNA
  • Publication number: 20210208808
    Abstract: Aspects of a storage device are provided which allow for partitioning of memory based on partition commands received from a host device. The storage device includes a memory configured to store data, and a controller configured to partition the memory into multiple partitions based on a partition command received from the host device. The controller is further configured to switch from a first partition to a second partition in response to a partition switching command received from the host device, and the controller may execute a command received from the host device on data associated with the second partition. When the controller receives the command from the host device associated with data including a logical address, the controller may update the logical address based on the second partition and execute the command based on the updated logical address.
    Type: Application
    Filed: January 22, 2020
    Publication date: July 8, 2021
    Inventors: Eshaan Gupta, Dharmaraju Marenahally Krishna, Abhinand Amarnath, Ashish Kumar
  • Patent number: 10553301
    Abstract: Non-volatile memory and processes for reprogramming data posing a potential reliability concern are provided. A process is provided for distinguishing between cross-temperature effects and read disturb effects as part of determining whether to perform a maintenance operation such as reprogramming. A process is provided that compensates for cross-temperature effects while testing to determine whether to perform a maintenance operation. Applying temperature compensation attempts to remove cross-temperature effects so that testing accurately detects whether read disturb has occurred, without the effects of temperature. By reducing cross-temperature effects, maintenance operations can be more accurately scheduled for memory that has experienced read disturb, as opposed to cross-temperature effects.
    Type: Grant
    Filed: August 15, 2017
    Date of Patent: February 4, 2020
    Assignee: SanDisk Technologies LLC
    Inventors: Narayan K, Sateesh Desireddi, Aneesh Puthoor, Dharmaraju Marenahally Krishna, Arun Thandapani, Divya Prasad, Thendral Murugaiyan, Piyush Dhotre
  • Patent number: 10535383
    Abstract: A die includes a plurality of memory cells. The die also includes a calculation circuit configured to determine a difference between a write temperature and a read temperature in response to a read request for user data stored in the memory cells. The die further includes a notification circuit configured to signal a cross-temperature condition in response to the difference satisfying a threshold.
    Type: Grant
    Filed: February 28, 2018
    Date of Patent: January 14, 2020
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Anantharaj Thalaimalaivanaraj, Suman Tenugu, Arun Thandapani, Dharmaraju Marenahally Krishna, Sainath Viswasarai
  • Publication number: 20190267054
    Abstract: A die includes a plurality of memory cells. The die also includes a calculation circuit configured to determine a difference between a write temperature and a read temperature in response to a read request for user data stored in the memory cells. The die further includes a notification circuit configured to signal a cross-temperature condition in response to the difference satisfying a threshold.
    Type: Application
    Filed: February 28, 2018
    Publication date: August 29, 2019
    Inventors: Anantharaj Thalaimalaivanaraj, Suman Tenugu, Arun Thandapani, Dharmaraju Marenahally Krishna, Sainath Viswasarai
  • Publication number: 20180350446
    Abstract: Non-volatile memory and processes for reprogramming data posing a potential reliability concern are provided. A process is provided for distinguishing between cross-temperature effects and read disturb effects as part of determining whether to perform a maintenance operation such as reprogramming. A process is provided that compensates for cross-temperature effects while testing to determine whether to perform a maintenance operation. Applying temperature compensation attempts to remove cross-temperature effects so that testing accurately detects whether read disturb has occurred, without the effects of temperature. By reducing cross-temperature effects, maintenance operations can be more accurately scheduled for memory that has experienced read disturb, as opposed to cross-temperature effects.
    Type: Application
    Filed: August 15, 2017
    Publication date: December 6, 2018
    Applicant: SanDisk Technologies LLC
    Inventors: Narayan K, Sateesh Desireddi, Aneesh Puthoor, Dharmaraju Marenahally Krishna, Arun Thandapani, Divya Prasad, Thendral Murugaiyan, Piyush Dhotre
  • Patent number: 9691485
    Abstract: A storage system and method for marginal write-abort detection using a memory parameter change is provided. In one embodiment, a method for detecting a write abort is provided that is performed in a storage system having a memory. The method comprises reading a lower page in memory; determining if any data is written in the lower page; and in response to determining that no data is written in the lower page: increasing source voltage for memory cells in the lower page; re-reading the lower page; determining if a read failure exists in the re-read lower page; and in response to determining that a read failure exists in the re-read lower page, detecting a write abort. Other embodiments are possible, and each of the embodiments can be used alone or together in combination.
    Type: Grant
    Filed: July 11, 2016
    Date of Patent: June 27, 2017
    Assignee: SANDISK TECHNOLOGIES LLC
    Inventors: Chittoor Devarajan Sunil Kumar, Divya Prasad, Piyush Anil Dhotre, Dharmaraju Marenahally Krishna, Thendral Murugaiyan, Arun Thandapani