Patents by Inventor Yasushi Nagadomi

Yasushi Nagadomi 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: 20170076804
    Abstract: A non-volatile semiconductor memory device includes a memory cell array and a control circuit. A control circuit performs an erase operation providing a memory cell with a first threshold voltage level for erasing data of a memory cell, and then perform a plurality of first write operations providing a memory cell with a second threshold voltage level, the second threshold voltage level being higher than the first threshold voltage level and being positive level. When the control circuit receives a first execution instruction from outside during the first write operations, the first execution instruction being for performing first function operation except for the erase operation and the first write operations, the circuit performs the first function operation during the first write operations.
    Type: Application
    Filed: November 28, 2016
    Publication date: March 16, 2017
    Applicant: Kabushiki Kaisha Toshiba
    Inventor: Yasushi NAGADOMI
  • Patent number: 9583200
    Abstract: A non-volatile semiconductor memory device includes a memory cell array and a control circuit. A control circuit performs an erase operation providing a memory cell with a first threshold voltage level for erasing data of a memory cell, and then perform a plurality of first write operations providing a memory cell with a second threshold voltage level, the second threshold voltage level being higher than the first threshold voltage level and being positive level. When the control circuit receives a first execution instruction from outside during the first write operations, the first execution instruction being for performing first function operation except for the erase operation and the first write operations, the circuit performs the first function operation during the first write operations.
    Type: Grant
    Filed: March 18, 2016
    Date of Patent: February 28, 2017
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventor: Yasushi Nagadomi
  • Publication number: 20160365154
    Abstract: A semiconductor memory device includes a memory cell, a sense amplifier connected to the memory cell, a first data latch that is connected to the sense amplifier and stores data of the memory cell, a second data latch that is connected to the sense amplifier and stores data of the memory cell, a third data latch that is connected to an input/output circuit, a fourth data latch that is connected to the input/output circuit, a first data bus of n-bit width that connects the sense amplifier, the first data latch, and the second data latch, and a second data bus of m-bit width that connects the third data latch and the fourth data latch to the first data bus, where m<n.
    Type: Application
    Filed: March 3, 2016
    Publication date: December 15, 2016
    Inventors: Yasushi NAGADOMI, Satoru HOSHI
  • Patent number: 9502116
    Abstract: According to one embodiment, a nonvolatile semiconductor memory apparatus includes a memory cell array, a row decoder, a controller. The memory cell array includes a plurality of memory strings. The memory strings include a first select transistor and a second select transistor, and are connected to each of a plurality of bit lines. The row decoder applies a voltage to the first and second select transistors. The controller detects a defect of the bit lines based on data read from the memory cells.
    Type: Grant
    Filed: December 23, 2014
    Date of Patent: November 22, 2016
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Naoya Tokiwa, Yasushi Nagadomi
  • Publication number: 20160203869
    Abstract: A non-volatile semiconductor memory device includes a memory cell array and a control circuit. A control circuit performs an erase operation providing a memory cell with a first threshold voltage level for erasing data of a memory cell, and then perform a plurality of first write operations providing a memory cell with a second threshold voltage level, the second threshold voltage level being higher than the first threshold voltage level and being positive level. When the control circuit receives a first execution instruction from outside during the first write operations, the first execution instruction being for performing first function operation except for the erase operation and the first write operations, the circuit performs the first function operation during the first write operations.
    Type: Application
    Filed: March 18, 2016
    Publication date: July 14, 2016
    Applicant: Kabushiki Kaisha Toshiba
    Inventor: Yasushi NAGADOMI
  • Publication number: 20160147455
    Abstract: A memory system includes a nonvolatile memory having a plurality of nonvolatile memory chips incorporated therein, a control circuit that controls the nonvolatile memory, an MPU that controls the control circuit, and an interface circuit that communicates with a host, all of which are mounted on a board of the memory system, and the memory system further includes a bus switch that switches connection of a signal line between the control circuit and the nonvolatile memory chips.
    Type: Application
    Filed: February 1, 2016
    Publication date: May 26, 2016
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Yasushi NAGADOMI
  • Patent number: 9330772
    Abstract: A non-volatile semiconductor memory device includes a memory cell array and a control circuit. A control circuit performs an erase operation providing a memory cell with a first threshold voltage level for erasing data of a memory cell, and then perform a plurality of first write operations providing a memory cell with a second threshold voltage level, the second threshold voltage level being higher than the first threshold voltage level and being positive level. When the control circuit receives a first execution instruction from outside during the first write operations, the first execution instruction being for performing first function operation except for the erase operation and the first write operations, the circuit performs the first function operation during the first write operations.
    Type: Grant
    Filed: June 24, 2015
    Date of Patent: May 3, 2016
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventor: Yasushi Nagadomi
  • Patent number: 9280461
    Abstract: A memory system includes a nonvolatile memory having a plurality of nonvolatile memory chips incorporated therein, a control circuit that controls the nonvolatile memory, an MPU that controls the control circuit, and an interface circuit that communicates with a host, all of which are mounted on a board of the memory system, and the memory system further includes a bus switch that switches connection of a signal line between the control circuit and the nonvolatile memory chips.
    Type: Grant
    Filed: July 18, 2014
    Date of Patent: March 8, 2016
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yasushi Nagadomi
  • Publication number: 20150294728
    Abstract: A non-volatile semiconductor memory device includes a memory cell array and a control circuit. A control circuit performs an erase operation providing a memory cell with a first threshold voltage level for erasing data of a memory cell, and then perform a plurality of first write operations providing a memory cell with a second threshold voltage level, the second threshold voltage level being higher than the first threshold voltage level and being positive level. When the control circuit receives a first execution instruction from outside during the first write operations, the first execution instruction being for performing first function operation except for the erase operation and the first write operations, the circuit performs the first function operation during the first write operations.
    Type: Application
    Filed: June 24, 2015
    Publication date: October 15, 2015
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Yasushi NAGADOMI
  • Patent number: 9075740
    Abstract: A memory system (10) is disclosed, which comprises a flash-EEPROM nonvolatile memory (11) having a plurality of memory cells that have floating gates and in which data items are electrically erasable and writable, a cache memory (13) that temporarily stores data of the flash-EEPROM nonvolatile memory (11), a control circuit (12, 14) that controls the flash-EEPROM nonvolatile memory (11) and the cache memory (13), and an interface circuit (16) that communicates with a host, in which the control circuit functions to read data from a desired target area to-be-determined of the flash-EEPROM nonvolatile memory and detect an erased area to determine a written area/unwritten area by using as a determination condition whether or not a count number of data “0” of the read data has reached a preset criterion count number.
    Type: Grant
    Filed: June 4, 2014
    Date of Patent: July 7, 2015
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yasushi Nagadomi, Daisaburo Takashima, Kosuke Hatsuda
  • Patent number: 9076536
    Abstract: A non-volatile semiconductor memory device includes a memory cell array and a control circuit. A control circuit performs an erase operation providing a memory cell with a first threshold voltage level for erasing data of a memory cell, and then perform a plurality of first write operations providing a memory cell with a second threshold voltage level, the second threshold voltage level being higher than the first threshold voltage level and being positive level. When the control circuit receives a first execution instruction from outside during the first write operations, the first execution instruction being for performing first function operation except for the erase operation and the first write operations, the circuit performs the first function operation during the first write operations.
    Type: Grant
    Filed: November 29, 2013
    Date of Patent: July 7, 2015
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventor: Yasushi Nagadomi
  • Publication number: 20150117102
    Abstract: According to one embodiment, a nonvolatile semiconductor memory apparatus includes a memory cell array, a row decoder, a controller. The memory cell array includes a plurality of memory strings. The memory strings include a first select transistor and a second select transistor, and are connected to each of a plurality of bit lines. The row decoder applies a voltage to the first and second select transistors. The controller detects a defect of the bit lines based on data read from the memory cells.
    Type: Application
    Filed: December 23, 2014
    Publication date: April 30, 2015
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Naoya TOKIWA, Yasushi NAGADOMI
  • Publication number: 20150070993
    Abstract: A nonvolatile semiconductor memory device according to an embodiment comprises: a memory string including a first memory cell and a second memory cell; a first word line connected to a gate of the first memory cell; a second word line connected to a gate of the second memory cell; and a peripheral circuit configured to control a write sequence and a read sequence, the peripheral circuit, during the write sequence or the read sequence on the first memory cell, executing a first operation on the condition that a positive first pass voltage is applied to the first word line and the second word line.
    Type: Application
    Filed: March 13, 2014
    Publication date: March 12, 2015
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Yasushi NAGADOMI
  • Patent number: 8947933
    Abstract: According to one embodiment, a nonvolatile semiconductor memory apparatus includes a memory cell array, a row decoder, a controller. The memory cell array includes a plurality of memory strings. The memory strings include a first select transistor and a second select transistor, and are connected to each of a plurality of bit lines. The row decoder applies a voltage to the first and second select transistors. The controller detects a defect of the bit lines based on data read from the memory cells.
    Type: Grant
    Filed: June 7, 2013
    Date of Patent: February 3, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Naoya Tokiwa, Yasushi Nagadomi
  • Patent number: 8885417
    Abstract: In writing, a first write operation to a first memory cell is executed; and a second write operation for providing a first threshold-voltage distribution to a second memory cell adjacent to the first one, is executed. The first threshold voltage distribution is a lowest threshold-voltage distribution among the positive threshold voltage distributions. It is verified whether a desired threshold voltage distribution has been obtained in the first memory cell or not (first write verify operation), moreover, it is verified whether a first threshold voltage distribution or a threshold voltage distribution having a voltage level larger than the first threshold-voltage distribution has been obtained in the second memory cell or not (second write verify operation). A control circuit outputs results of the first write verify operation and the second write verify operation.
    Type: Grant
    Filed: October 4, 2013
    Date of Patent: November 11, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yasushi Nagadomi, Naoya Tokiwa
  • Publication number: 20140331005
    Abstract: A memory system includes a nonvolatile memory having a plurality of nonvolatile memory chips incorporated therein, a control circuit that controls the nonvolatile memory, an MPU that controls the control circuit, and an interface circuit that communicates with a host, all of which are mounted on a board of the memory system, and the memory system further includes a bus switch that switches connection of a signal line between the control circuit and the nonvolatile memory chips.
    Type: Application
    Filed: July 18, 2014
    Publication date: November 6, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Yasushi NAGADOMI
  • Publication number: 20140289588
    Abstract: A memory system (10) is disclosed, which comprises a flash-EEPROM nonvolatile memory (11) having a plurality of memory cells that have floating gates and in which data items are electrically erasable and writable, a cache memory (13) that temporarily stores data of the flash-EEPROM nonvolatile memory (11), a control circuit (12, 14) that controls the flash-EEPROM nonvolatile memory (11) and the cache memory (13), and an interface circuit (16) that communicates with a host, in which the control circuit functions to read data from a desired target area to-be-determined of the flash-EEPROM nonvolatile memory and detect an erased area to determine a written area/unwritten area by using as a determination condition whether or not a count number of data “0” of the read data has reached a preset criterion count number.
    Type: Application
    Filed: June 4, 2014
    Publication date: September 25, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yasushi NAGADOMI, Daisaburo Takashima, Kosuke Hatsuda
  • Patent number: 8832362
    Abstract: A memory system includes a nonvolatile memory having a plurality of nonvolatile memory chips incorporated therein, a control circuit that controls the nonvolatile memory, an MPU that controls the control circuit, and an interface circuit that communicates with a host, all of which are mounted on a board of the memory system, and the memory system further includes a bus switch that switches connection of a signal line between the control circuit and the nonvolatile memory chips.
    Type: Grant
    Filed: October 25, 2013
    Date of Patent: September 9, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yasushi Nagadomi
  • Patent number: 8732553
    Abstract: The embodiments include an error correction processing unit and an error correction history recording unit. The error correction processing unit performs an error correction process based on data read from a non-volatile semiconductor memory and a second-step error correction code corresponding to the data. The error correction history recording unit records error correction history indicating whether first error correction is successful through the first error correction process, in association with unit data. When error correction history of target unit data to be read indicates that correction is not successful, the second error correction process is executed without executing the first error correction process.
    Type: Grant
    Filed: September 21, 2011
    Date of Patent: May 20, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yasushi Nagadomi, Daisaburo Takashima
  • Publication number: 20140098609
    Abstract: According to one embodiment, a nonvolatile semiconductor memory apparatus includes a memory cell array, a row decoder, a controller. The memory cell array includes a plurality of memory strings. The memory strings include a first select transistor and a second select transistor, and are connected to each of a plurality of bit lines. The row decoder applies a voltage to the first and second select transistors. The controller detects a defect of the bit lines based on data read from the memory cells.
    Type: Application
    Filed: June 7, 2013
    Publication date: April 10, 2014
    Inventors: Naoya TOKIWA, Yasushi NAGADOMI