Patents by Inventor Daisuke Kouno

Daisuke Kouno 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: 9928915
    Abstract: For data erase from an electrically erasable and programmable non-volatile memory cell, the following operations are performed: an erase operation to apply an erase pulse voltage to a memory cell for data erase, an erase verify operation to verify whether data erase is completed, and a step-up operation to increase the erase pulse voltage by a certain step-up voltage if data erase is not completed. A control unit controls voltages so that at least a first erase pulse voltage initially generated in the erase operation has a longer rise time than that of a second erase pulse voltage generated subsequent to the first erase pulse voltage.
    Type: Grant
    Filed: October 21, 2016
    Date of Patent: March 27, 2018
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Yasuhiro Shiino, Daisuke Kouno, Shigefumi Irieda, Kenri Nakai, Eietsu Takahashi
  • Publication number: 20170040062
    Abstract: For data erase from an electrically erasable and programmable non-volatile memory cell, the following operations are performed: an erase operation to apply an erase pulse voltage to a memory cell for data erase, an erase verify operation to verify whether data erase is completed, and a step-up operation to increase the erase pulse voltage by a certain step-up voltage if data erase is not completed. A control unit controls voltages so that at least a first erase pulse voltage initially generated in the erase operation has a longer rise time than that of a second erase pulse voltage generated subsequent to the first erase pulse voltage.
    Type: Application
    Filed: October 21, 2016
    Publication date: February 9, 2017
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yasuhiro SHIINO, Daisuke KOUNO, Shigefumi IRIEDA, Kenri NAKAI, Eietsu TAKAHASHI
  • Patent number: 9508442
    Abstract: For data erase from an electrically erasable and programmable non-volatile memory cell, the following operations are performed: an erase operation to apply an erase pulse voltage to a memory cell for data erase, an erase verify operation to verify whether data erase is completed, and a step-up operation to increase the erase pulse voltage by a certain step-up voltage if data erase is not completed. A control unit controls voltages so that at least a first erase pulse voltage initially generated in the erase operation has a longer rise time than that of a second erase pulse voltage generated subsequent to the first erase pulse voltage.
    Type: Grant
    Filed: January 7, 2016
    Date of Patent: November 29, 2016
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yasuhiro Shiino, Daisuke Kouno, Shigefumi Irieda, Kenri Nakai, Eietsu Takahashi
  • Publication number: 20160118127
    Abstract: For data erase from an electrically erasable and programmable non-volatile memory cell, the following operations are performed: an erase operation to apply an erase pulse voltage to a memory cell for data erase, an erase verify operation to verify whether data erase is completed, and a step-up operation to increase the erase pulse voltage by a certain step-up voltage if data erase is not completed. A control unit controls voltages so that at least a first erase pulse voltage initially generated in the erase operation has a longer rise time than that of a second erase pulse voltage generated subsequent to the first erase pulse voltage.
    Type: Application
    Filed: January 7, 2016
    Publication date: April 28, 2016
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yasuhiro Shiino, Daisuke Kouno, Shigefumi Irieda, Kenri Nakai, Eietsu Takahashi
  • Patent number: 9263140
    Abstract: For data erase from an electrically erasable and programmable non-volatile memory cell, the following operations are performed: an erase operation to apply an erase pulse voltage to a memory cell for data erase, an erase verify operation to verify whether data erase is completed, and a step-up operation to increase the erase pulse voltage by a certain step-up voltage if data erase is not completed. A control unit controls voltages so that at least a first erase pulse voltage initially generated in the erase operation has a longer rise time than that of a second erase pulse voltage generated subsequent to the first erase pulse voltage.
    Type: Grant
    Filed: May 15, 2014
    Date of Patent: February 16, 2016
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yasuhiro Shiino, Daisuke Kouno, Shigefumi Irieda, Kenri Nakai, Eietsu Takahashi
  • Patent number: 8848447
    Abstract: A nonvolatile semiconductor memory device in accordance with an embodiment includes: a memory cell array having electrically rewritable nonvolatile memory cells; and a control unit. The control unit performs control of repeating a write operation, a write verify operation, and a step-up operation, the write verify operation being an operation to verify whether data write is completed or not, and the step-up operation being an operation to raise the write pulse voltage if data write is not completed. The control unit, during the write operation, raises a first write pulse voltage with a first gradient, and then raises a second write pulse voltage with a second gradient, thereby executing the write operation, the first write pulse voltage including at least a write pulse voltage generated at first, the second write pulse voltage being generated after the first write pulse voltage, and the second gradient being larger than the first gradient.
    Type: Grant
    Filed: September 7, 2011
    Date of Patent: September 30, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yasuhiro Shiino, Daisuke Kouno, Shigefumi Irieda, Kenri Nakai, Eietsu Takahashi
  • Publication number: 20140254282
    Abstract: For data erase from an electrically erasable and programmable non-volatile memory cell, the following operations are performed: an erase operation to apply an erase pulse voltage to a memory cell for data erase, an erase verify operation to verify whether data erase is completed, and a step-up operation to increase the erase pulse voltage by a certain step-up voltage if data erase is not completed. A control unit controls voltages so that at least a first erase pulse voltage initially generated in the erase operation has a longer rise time than that of a second erase pulse voltage generated subsequent to the first erase pulse voltage.
    Type: Application
    Filed: May 15, 2014
    Publication date: September 11, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yasuhiro SHIINO, Daisuke KOUNO, Shigefumi IRIEDA, Kenri NAKAI, Eietsu TAKAHASHI
  • Patent number: 8767478
    Abstract: For data erase from an electrically erasable and programmable non-volatile memory cell, the following operations are performed: an erase operation to apply an erase pulse voltage to a memory cell for data erase, an erase verify operation to verify whether data erase is completed, and a step-up operation to increase the erase pulse voltage by a certain step-up voltage if data erase is not completed. A control unit controls voltages so that at least a first erase pulse voltage initially generated in the erase operation has a longer rise time than that of a second erase pulse voltage generated subsequent to the first erase pulse voltage.
    Type: Grant
    Filed: July 15, 2013
    Date of Patent: July 1, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yasuhiro Shiino, Daisuke Kouno, Shigefumi Irieda, Kenri Nakai, Eietsu Takahashi
  • Publication number: 20130301359
    Abstract: For data erase from an electrically erasable and programmable non-volatile memory cell, the following operations are performed: an erase operation to apply an erase pulse voltage to a memory cell for data erase, an erase verify operation to verify whether data erase is completed, and a step-up operation to increase the erase pulse voltage by a certain step-up voltage if data erase is not completed. A control unit controls voltages so that at least a first erase pulse voltage initially generated in the erase operation has a longer rise time than that of a second erase pulse voltage generated subsequent to the first erase pulse voltage.
    Type: Application
    Filed: July 15, 2013
    Publication date: November 14, 2013
    Inventors: Yasuhiro SHIINO, Daisuke KOUNO, Shigefumi IRIEDA, Kenri NAKAI, Eietsu TAKAHASHI
  • Patent number: 8531891
    Abstract: For data erase from an electrically erasable and programmable non-volatile memory cell, the following operations are performed: an erase operation to apply an erase pulse voltage to a memory cell for data erase, an erase verify operation to verify whether data erase is completed, and a step-up operation to increase the erase pulse voltage by a certain step-up voltage if data erase is not completed. A control unit controls voltages so that at least a first erase pulse voltage initially generated in the erase operation has a longer rise time than that of a second erase pulse voltage generated subsequent to the first erase pulse voltage.
    Type: Grant
    Filed: January 10, 2012
    Date of Patent: September 10, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yasuhiro Shiino, Daisuke Kouno, Shigefumi Irieda, Kenri Nakai, Eietsu Takahashi
  • Publication number: 20120281477
    Abstract: According to one embodiment, a semiconductor memory device includes a memory cell array includes a plurality of cell units each composed of a plurality of memory cells which are arranged at intersections of a plurality of bit lines and a plurality of word lines and whose current paths are connected in series and select transistors each connected to either end of the series connection, a voltage generator circuit which generates a voltage applied to the memory cell array, and a control circuit which controls the memory cell array and the voltage generator circuit.
    Type: Application
    Filed: December 1, 2011
    Publication date: November 8, 2012
    Inventors: Manabu Sakaniwa, Koki Ueno, Shigefumi Irieda, Eietsu Takahashi, Yasuhiro Shiino, Daisuke Kouno
  • Publication number: 20120106257
    Abstract: For data erase from an electrically erasable and programmable non-volatile memory cell, the following operations are performed: an erase operation to apply an erase pulse voltage to a memory cell for data erase, an erase verify operation to verify whether data erase is completed, and a step-up operation to increase the erase pulse voltage by a certain step-up voltage if data erase is not completed. A control unit controls voltages so that at least a first erase pulse voltage initially generated in the erase operation has a longer rise time than that of a second erase pulse voltage generated subsequent to the first erase pulse voltage.
    Type: Application
    Filed: January 10, 2012
    Publication date: May 3, 2012
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Yasuhiro SHIINO, Daisuke Kouno, Shigefumi Irieda, Kenri Nakai, Eietsu Takahashi
  • Patent number: 8149631
    Abstract: For data erase from an electrically erasable and programmable non-volatile memory cell, the following operations are performed: an erase operation to apply an erase pulse voltage to a memory cell for data erase, an erase verify operation to verify whether data erase is completed, and a step-up operation to increase the erase pulse voltage by a certain step-up voltage if data erase is not completed. A control unit controls voltages so that at least a first erase pulse voltage initially generated in the erase operation has a longer rise time than that of a second erase pulse voltage generated subsequent to the first erase pulse voltage.
    Type: Grant
    Filed: June 9, 2010
    Date of Patent: April 3, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yasuhiro Shiino, Daisuke Kouno, Shigefumi Irieda, Kenri Nakai, Eietsu Takahashi
  • Publication number: 20120072648
    Abstract: A nonvolatile semiconductor memory device in accordance with an embodiment includes: a memory cell array having electrically rewritable nonvolatile memory cells; and a control unit. The control unit performs control of repeating a write operation, a write verify operation, and a step-up operation, the write verify operation being an operation to verify whether data write is completed or not, and the step-up operation being an operation to raise the write pulse voltage if data write is not completed. The control unit, during the write operation, raises a first write pulse voltage with a first gradient, and then raises a second write pulse voltage with a second gradient, thereby executing the write operation, the first write pulse voltage including at least a write pulse voltage generated at first, the second write pulse voltage being generated after the first write pulse voltage, and the second gradient being larger than the first gradient.
    Type: Application
    Filed: September 7, 2011
    Publication date: March 22, 2012
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Yasuhiro SHIINO, Daisuke Kouno, Shigefumi Irieda, Kenri Nakai, Eietsu Takahashi
  • Publication number: 20110013461
    Abstract: For data erase from an electrically erasable and programmable non-volatile memory cell, the following operations are performed: an erase operation to apply an erase pulse voltage to a memory cell for data erase, an erase verify operation to verify whether data erase is completed, and a step-up operation to increase the erase pulse voltage by a certain step-up voltage if data erase is not completed. A control unit controls voltages so that at least a first erase pulse voltage initially generated in the erase operation has a longer rise time than that of a second erase pulse voltage generated subsequent to the first erase pulse voltage.
    Type: Application
    Filed: June 9, 2010
    Publication date: January 20, 2011
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yasuhiro SHIINO, Daisuke Kouno, Shigefumi Irieda, Kenri Nakai, Eietsu Takahashi