Patents by Inventor Atsushi Shikata

Atsushi Shikata 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: 6584015
    Abstract: A semiconductor storage device that determines the cause of an error at the time of the error correction of data read out from a non-volatile semiconductor memory, on the basis of a previously recorded error correction count, and selects a data refresh processing or a substitute processing to perform. When the error is detected, the corrected data is rewritten back for preventing reoccurrence of error due to accidental cause. If it is determined that the reoccurrence frequency of the error is high and the error is due to degradation of the storage medium, based on the error correction count, the substitute processing is performed.
    Type: Grant
    Filed: September 19, 2002
    Date of Patent: June 24, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Kunihiro Katayama, Takayuki Tamura, Yusuke Jono, Motoki Kanamori, Atsushi Shikata
  • Publication number: 20030048659
    Abstract: In a card storage device containing a non-volatile memory and a buffer memory, the buffer memory includes a plurality of banks. Data is transferred sequentially from a host CPU to the banks of the buffer memory, data is transferred to the non-volatile memory from a bank that becomes full, a write operation is started when one unit of data to be written into the non-volatile memory at a time has been transferred and, without waiting for the data to be written, the next write data is transferred from the host CPU to a bank from which write data has been transferred.
    Type: Application
    Filed: February 26, 2002
    Publication date: March 13, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Motoki Kanamori, Takayuki Tamura, Kenji Kozakai, Atsushi Shikata, Shinsuke Asari
  • Publication number: 20030051094
    Abstract: A memory card is provided with a transfer control circuit, a write control circuit and a judging circuit. The transfer control circuit outputs a transfer flag signal during the data transfer. The write control circuit outputs an internal busy signal during the data write operation. The judging circuit outputs a transfer interruption signal when a card selection signal of the host is negated during the input of the transfer flat signal and also outputs a suspension signal when the card selection signal is negated during the input of the internal busy signal. A CPU invalidates the data being transfer to interrupt the transfer process upon reception of the transfer interruption signal and completes, upon reception of the suspension signal, the process being executed and stays in the waiting condition.
    Type: Application
    Filed: July 16, 2002
    Publication date: March 13, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Kunihiro Katayama, Motoki Kanamori, Atsushi Shikata, Hidefumi Oodate, Atsushi Shiraishi
  • Publication number: 20030043647
    Abstract: When a non-volatile memory write error occurs in a card storage device containing a non-volatile memory and an error correction circuit, write data is read from the non-volatile memory and a check is made if the error can be corrected by the error correction circuit. If the error can be corrected, the write operation is ended. If the error correction circuit cannot correct the error, substitute processing is performed to write data into some other area.
    Type: Application
    Filed: February 21, 2002
    Publication date: March 6, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Motoki Kanamori, Kunihiro Katayama, Atsushi Shiraishi, Shigeo Kurakata, Atsushi Shikata
  • Publication number: 20030021151
    Abstract: In the conventional nonvolatile memory, it is not possible to determine the cause of the error is accidental or due to the degradation when the error is detect at the time of data read. Therefore, unnecessary substitute processing is performed, resulting in the exhaustion of the substitute area to shorten the life of the storage device.
    Type: Application
    Filed: September 19, 2002
    Publication date: January 30, 2003
    Inventors: Kunihiro Katayama, Takayuki Tamura, Yusuke Jono, Motoki Kanamori, Atsushi Shikata
  • Patent number: 6480416
    Abstract: A semiconductor storage device that determines the cause of an error at the time of the error correction of data read out from a non-volatile semiconductor memory, on the basis of a previously recorded error correction count, and selects a data refresh processing or a substitute processing to perform. When the error is detected, the corrected data is rewritten back for preventing reoccurrence of error due to accidental cause. If it is determined that the reoccurrence frequency of the error is high and the error is due to degradation of the storage medium, based on the error correction count, the substitute processing is performed.
    Type: Grant
    Filed: December 18, 2001
    Date of Patent: November 12, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Kunihiro Katayama, Takayuki Tamura, Yusuke Jono, Motoki Kanamori, Atsushi Shikata
  • Publication number: 20020080650
    Abstract: In the conventional nonvolatile memory, it is not possible to determine the cause of the error is accidental or due to the degradation when the error is detect at the time of data read. Therefore, unnecessary substitute processing is performed, resulting in the exhaustion of the substitute area to shorten the life of the storage device.
    Type: Application
    Filed: December 18, 2001
    Publication date: June 27, 2002
    Inventors: Kunihiro Katayama, Takayuki Tamura, Yusuke Jono, Motoki Kanamori, Atsushi Shikata
  • Patent number: 6339546
    Abstract: A semiconductor storage device that determines the cause of an error at the time of the error correction of data read out from a non-volatile semiconductor memory, on the basis of a previously recorded error correction count, and selects a data refresh processing or a substitute processing to perform. When the error is detected, the corrected data is rewritten back for preventing reoccurrence of error due to accidental cause. If it is determined that the reoccurrence frequency of the error is high and the error is due to degradation of the storage medium, based on the error correction count, the substitute processing is performed.
    Type: Grant
    Filed: September 15, 2000
    Date of Patent: January 15, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Kunihiro Katayama, Takayuki Tamura, Yusuke Jono, Motoki Kanamori, Atsushi Shikata