Patents by Inventor Akira Yamaga

Akira Yamaga 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: 20230420052
    Abstract: A memory system includes a semiconductor memory device having memory cells arranged in rows and columns, and a controller configured to issue a write command with or without a partial page program command to the semiconductor memory device. The semiconductor memory device, in response to the write command issued without the partial page command, executes a first program operation on a page of memory cells and then a first verify operation on the memory cells of the page using a first verify voltage for all of the memory cells of the page, and in response to the write command issued with the partial page command, executes a second program operation on a subset of the memory cells of the page and then a second verify operation on the memory cells of the subset using one of several different second verify voltages corresponding to the subset.
    Type: Application
    Filed: September 13, 2023
    Publication date: December 28, 2023
    Inventors: Masanobu SHIRAKAWA, Kenta YASUFUKU, Akira YAMAGA
  • Patent number: 11804267
    Abstract: A memory system includes a semiconductor memory device having memory cells arranged in rows and columns, and a controller configured to issue a write command with or without a partial page program command to the semiconductor memory device. The semiconductor memory device, in response to the write command issued without the partial page command, executes a first program operation on a page of memory cells and then a first verify operation on the memory cells of the page using a first verify voltage for all of the memory cells of the page, and in response to the write command issued with the partial page command, executes a second program operation on a subset of the memory cells of the page and then a second verify operation on the memory cells of the subset using one of several different second verify voltages corresponding to the subset.
    Type: Grant
    Filed: June 29, 2022
    Date of Patent: October 31, 2023
    Assignee: Kioxia Corporation
    Inventors: Masanobu Shirakawa, Kenta Yasufuku, Akira Yamaga
  • Publication number: 20220328103
    Abstract: A memory system includes a semiconductor memory device having memory cells arranged in rows and columns, and a controller configured to issue a write command with or without a partial page program command to the semiconductor memory device. The semiconductor memory device, in response to the write command issued without the partial page command, executes a first program operation on a page of memory cells and then a first verify operation on the memory cells of the page using a first verify voltage for all of the memory cells of the page, and in response to the write command issued with the partial page command, executes a second program operation on a subset of the memory cells of the page and then a second verify operation on the memory cells of the subset using one of several different second verify voltages corresponding to the subset.
    Type: Application
    Filed: June 29, 2022
    Publication date: October 13, 2022
    Inventors: Masanobu SHIRAKAWA, Kenta YASUFUKU, Akira YAMAGA
  • Patent number: 11410732
    Abstract: A memory system includes a semiconductor memory device having memory cells arranged in rows and columns, and a controller configured to issue a write command with or without a partial page program command to the semiconductor memory device. The semiconductor memory device, in response to the write command issued without the partial page command, executes a first program operation on a page of memory cells and then a first verify operation on the memory cells of the page using a first verify voltage for all of the memory cells of the page, and in response to the write command issued with the partial page command, executes a second program operation on a subset of the memory cells of the page and then a second verify operation on the memory cells of the subset using one of several different second verify voltages corresponding to the subset.
    Type: Grant
    Filed: March 9, 2021
    Date of Patent: August 9, 2022
    Assignee: KIOXIA CORPORATION
    Inventors: Masanobu Shirakawa, Kenta Yasufuku, Akira Yamaga
  • Publication number: 20210193228
    Abstract: A memory system includes a semiconductor memory device having memory cells arranged in rows and columns, and a controller configured to issue a write command with or without a partial page program command to the semiconductor memory device. The semiconductor memory device, in response to the write command issued without the partial page command, executes a first program operation on a page of memory cells and then a first verify operation on the memory cells of the page using a first verify voltage for all of the memory cells of the page, and in response to the write command issued with the partial page command, executes a second program operation on a subset of the memory cells of the page and then a second verify operation on the memory cells of the subset using one of several different second verify voltages corresponding to the subset.
    Type: Application
    Filed: March 9, 2021
    Publication date: June 24, 2021
    Inventors: Masanobu SHIRAKAWA, Kenta YASUFUKU, Akira YAMAGA
  • Patent number: 10978157
    Abstract: A memory system includes a semiconductor memory device having memory cells arranged in rows and columns, and a controller configured to issue a write command with or without a partial page program command to the semiconductor memory device. The semiconductor memory device, in response to the write command issued without the partial page command, executes a first program operation on a page of memory cells and then a first verify operation on the memory cells of the page using a first verify voltage for all of the memory cells of the page, and in response to the write command issued with the partial page command, executes a second program operation on a subset of the memory cells of the page and then a second verify operation on the memory cells of the subset using one of several different second verify voltages corresponding to the subset.
    Type: Grant
    Filed: February 14, 2020
    Date of Patent: April 13, 2021
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Masanobu Shirakawa, Kenta Yasufuku, Akira Yamaga
  • Publication number: 20200185036
    Abstract: A memory system includes a semiconductor memory device having memory cells arranged in rows and columns, and a controller configured to issue a write command with or without a partial page program command to the semiconductor memory device. The semiconductor memory device, in response to the write command issued without the partial page command, executes a first program operation on a page of memory cells and then a first verify operation on the memory cells of the page using a first verify voltage for all of the memory cells of the page, and in response to the write command issued with the partial page command, executes a second program operation on a subset of the memory cells of the page and then a second verify operation on the memory cells of the subset using one of several different second verify voltages corresponding to the subset.
    Type: Application
    Filed: February 14, 2020
    Publication date: June 11, 2020
    Inventors: Masanobu SHIRAKAWA, Kenta YASUFUKU, Akira YAMAGA
  • Patent number: 10600485
    Abstract: A memory system includes a semiconductor memory device having memory cells arranged in rows and columns, and a controller configured to issue a write command with or without a partial page program command to the semiconductor memory device. The semiconductor memory device, in response to the write command issued without the partial page command, executes a first program operation on a page of memory cells and then a first verify operation on the memory cells of the page using a first verify voltage for all of the memory cells of the page, and in response to the write command issued with the partial page command, executes a second program operation on a subset of the memory cells of the page and then a second verify operation on the memory cells of the subset using one of several different second verify voltages corresponding to the subset.
    Type: Grant
    Filed: March 15, 2019
    Date of Patent: March 24, 2020
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Masanobu Shirakawa, Kenta Yasufuku, Akira Yamaga
  • Patent number: 10574272
    Abstract: A memory system includes a nonvolatile memory and a memory controller configured to perform reading of a concatenation code from the nonvolatile memory in response to an external command, the memory controller including a decoder circuit which decodes a reception word in the concatenation code. The decoder circuit includes a first external code decoder that performs decoding on an external code portion, an internal code in-error bit estimation unit that performs estimation of an in-error bit on a bit sequence from the first external code decoder, based on a rule for an internal code in the concatenation code, and outputs a set of in-error bits that is obtained by the estimation, and a second external code decoder that performs decoding which uses the set of in-error bits that is output from the internal code in-error bit estimation unit, on the bit sequence from the first external code decoder.
    Type: Grant
    Filed: March 1, 2018
    Date of Patent: February 25, 2020
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Yuta Kumano, Kazumasa Yamamoto, Hironori Uchikawa, Akira Yamaga
  • Publication number: 20190214090
    Abstract: A memory system includes a semiconductor memory device having memory cells arranged in rows and columns, and a controller configured to issue a write command with or without a partial page program command to the semiconductor memory device. The semiconductor memory device, in response to the write command issued without the partial page command, executes a first program operation on a page of memory cells and then a first verify operation on the memory cells of the page using a first verify voltage for all of the memory cells of the page, and in response to the write command issued with the partial page command, executes a second program operation on a subset of the memory cells of the page and then a second verify operation on the memory cells of the subset using one of several different second verify voltages corresponding to the subset.
    Type: Application
    Filed: March 15, 2019
    Publication date: July 11, 2019
    Inventors: Masanobu SHIRAKAWA, Kenta YASUFUKU, Akira YAMAGA
  • Patent number: 10276243
    Abstract: A memory system includes a semiconductor memory device having memory cells arranged in rows and columns, and a controller configured to issue a write command with or without a partial page program command to the semiconductor memory device. The semiconductor memory device, in response to the write command issued without the partial page command, executes a first program operation on a page of memory cells and then a first verify operation on the memory cells of the page using a first verify voltage for all of the memory cells of the page, and in response to the write command issued with the partial page command, executes a second program operation on a subset of the memory cells of the page and then a second verify operation on the memory cells of the subset using one of several different second verify voltages corresponding to the subset.
    Type: Grant
    Filed: January 22, 2018
    Date of Patent: April 30, 2019
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Masanobu Shirakawa, Kenta Yasufuku, Akira Yamaga
  • Publication number: 20190089384
    Abstract: A memory system includes a nonvolatile memory and a memory controller configured to perform reading of a concatenation code from the nonvolatile memory in response to an external command, the memory controller including a decoder circuit which decodes a reception word in the concatenation code. The decoder circuit includes a first external code decoder that performs decoding on an external code portion, an internal code in-error bit estimation unit that performs estimation of an in-error bit on a bit sequence from the first external code decoder, based on a rule for an internal code in the concatenation code, and outputs a set of in-error bits that is obtained by the estimation, and a second external code decoder that performs decoding which uses the set of in-error bits that is output from the internal code in-error bit estimation unit, on the bit sequence from the first external code decoder.
    Type: Application
    Filed: March 1, 2018
    Publication date: March 21, 2019
    Inventors: Yuta KUMANO, Kazumasa YAMAMOTO, Hironori UCHIKAWA, Akira YAMAGA
  • Patent number: 10089241
    Abstract: According to one embodiment, a controller writes either processed data or preprocessing data and flags into each page included in m pages. The processed data is data after first data translation of write data to be written into a relevant page. The preprocessing data is data before the first data translation of the write data to be written into the relevant page. Each of the flag at least represents whether or not the first data translation is performed for write data to be written into the relevant page.
    Type: Grant
    Filed: September 12, 2016
    Date of Patent: October 2, 2018
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Tokumasa Hara, Osamu Torii, Kiichi Tachi, Susumu Tamon, Shigefumi Irieda, Juan Shi, Hironori Uchikawa, Kejen Lin, Akira Yamaga
  • Patent number: 10061691
    Abstract: According to one embodiment, a controller writes first processed data acquired by a first process into a nonvolatile memory during a first period. The controller writes second processed data acquired by a second process into the nonvolatile memory during a second period. The first process is for the purpose of improving the endurance of memory cells. The second process is for the purpose of decreasing inter-cell interferences between adjacent cells.
    Type: Grant
    Filed: March 15, 2017
    Date of Patent: August 28, 2018
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Kejen Lin, Tokumasa Hara, Hironori Uchikawa, Juan Shi, Akira Yamaga, Sho Kodama, Keiri Nakanishi
  • Publication number: 20180144801
    Abstract: A memory system includes a semiconductor memory device having memory cells arranged in rows and columns, and a controller configured to issue a write command with or without a partial page program command to the semiconductor memory device. The semiconductor memory device, in response to the write command issued without the partial page command, executes a first program operation on a page of memory cells and then a first verify operation on the memory cells of the page using a first verify voltage for all of the memory cells of the page, and in response to the write command issued with the partial page command, executes a second program operation on a subset of the memory cells of the page and then a second verify operation on the memory cells of the subset using one of several different second verify voltages corresponding to the subset.
    Type: Application
    Filed: January 22, 2018
    Publication date: May 24, 2018
    Applicant: Toshiba Memory Corporation
    Inventors: Masanobu SHIRAKAWA, Kenta YASUFUKU, Akira YAMAGA
  • Publication number: 20180068719
    Abstract: According to one embodiment, a controller writes first processed data acquired by a first process into a nonvolatile memory during a first period. The controller writes second processed data acquired by a second process into the nonvolatile memory during a second period. The first process is for the purpose of improving the endurance of memory cells. The second process is for the purpose of decreasing inter-cell interferences between adjacent cells.
    Type: Application
    Filed: March 15, 2017
    Publication date: March 8, 2018
    Applicant: Toshiba Memory Corporation
    Inventors: Kejen LIN, Tokumasa HARA, Hironori UCHIKAWA, Juan SHI, Akira YAMAGA, Sho KODAMA, Keiri NAKANISHI
  • Patent number: 9911498
    Abstract: A memory system includes a semiconductor memory device having memory cells arranged in rows and columns, and a controller configured to issue a write command with or without a partial page program command to the semiconductor memory device. The semiconductor memory device, in response to the write command issued without the partial page command, executes a first program operation on a page of memory cells and then a first verify operation on the memory cells of the page using a first verify voltage for all of the memory cells of the page, and in response to the write command issued with the partial page command, executes a second program operation on a subset of the memory cells of the page and then a second verify operation on the memory cells of the subset using one of several different second verify voltages corresponding to the subset.
    Type: Grant
    Filed: May 5, 2017
    Date of Patent: March 6, 2018
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Masanobu Shirakawa, Kenta Yasufuku, Akira Yamaga
  • Publication number: 20170262379
    Abstract: According to one embodiment, a controller writes either processed data or preprocessing data and flags into each page included in m pages. The processed data is data after first data translation of write data to be written into a relevant page. The preprocessing data is data before the first data translation of the write data to be written into the relevant page. Each of the flag at least represents whether or not the first data translation is performed for write data to be written into the relevant page.
    Type: Application
    Filed: September 12, 2016
    Publication date: September 14, 2017
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Tokumasa HARA, Osamu Torii, Kiichi Tachi, Susumu Tamon, Shigefumi Irieda, Juan Shi, Hironori Uchikawa, Kejen Lin, Akira Yamaga
  • Publication number: 20170243657
    Abstract: A memory system includes a semiconductor memory device having memory cells arranged in rows and columns, and a controller configured to issue a write command with or without a partial page program command to the semiconductor memory device. The semiconductor memory device, in response to the write command issued without the partial page command, executes a first program operation on a page of memory cells and then a first verify operation on the memory cells of the page using a first verify voltage for all of the memory cells of the page, and in response to the write command issued with the partial page command, executes a second program operation on a subset of the memory cells of the page and then a second verify operation on the memory cells of the subset using one of several different second verify voltages corresponding to the subset.
    Type: Application
    Filed: May 5, 2017
    Publication date: August 24, 2017
    Inventors: Masanobu SHIRAKAWA, Kenta YASUFUKU, Akira YAMAGA
  • Patent number: 9721666
    Abstract: A memory system includes a semiconductor memory device having memory cells arranged in rows and columns, and a controller configured to issue a write command with or without a partial page program command to the semiconductor memory device. The semiconductor memory device, in response to the write command issued without the partial page command, executes a first program operation on a page of memory cells and then a first verify operation on the memory cells of the page using a first verify voltage for all of the memory cells of the page, and in response to the write command issued with the partial page command, executes a second program operation on a subset of the memory cells of the page and then a second verify operation on the memory cells of the subset using one of several different second verify voltages corresponding to the subset.
    Type: Grant
    Filed: June 6, 2016
    Date of Patent: August 1, 2017
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Masanobu Shirakawa, Kenta Yasufuku, Akira Yamaga