Patents by Inventor Katuhiro Mori

Katuhiro Mori 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: 7286434
    Abstract: A semiconductor memory device with low power consumption in driving control signals of shift registers. The device contains a plurality of memory cell arrays each composed of a predetermined number of rows of memory cells. One set of shift registers are coupled to each cell array, and the nth set of shift registers successively activate word line selection signals according to a given control signal, so that the corresponding word lines of the nth cell array will be refreshed. Also coupled to each cell array is a shift register controller. The nth shift register controller provides a control signal to the nth set of shift registers when the nth cell array is being refreshed. When the refresh of that cell array is finished, the nth shift register controller forwards the control signal to the (n+1)th set of shift registers, thus initiating refresh operation for the (n+1)th cell array.
    Type: Grant
    Filed: July 14, 2006
    Date of Patent: October 23, 2007
    Assignee: Fujitsu Limited
    Inventors: Kaoru Mori, Katuhiro Mori, Shinichi Yamada, Kuninori Kawabata, Shigemasa Ito
  • Patent number: 7145825
    Abstract: A semiconductor memory device with low power consumption in driving control signals of shift registers. The device contains a plurality of memory cell arrays each composed of a predetermined number of rows of memory cells. One set of shift registers are coupled to each cell array, and the nth set of shift registers successively activate word line selection signals according to a given control signal, so that the corresponding word lines of the nth cell array will be refreshed. Also coupled to each cell array is a shift register controller. The nth shift register controller provides a control signal to the nth set of shift registers when the nth cell array is being refreshed. When the refresh of that cell array is finished, the nth shift register controller forwards the control signal to the (n+1)th set of shift registers, thus initiating refresh operation for the (n+1)th cell array.
    Type: Grant
    Filed: March 16, 2004
    Date of Patent: December 5, 2006
    Assignee: Fujitsu Limited
    Inventors: Kaoru Mori, Katuhiro Mori, Shinichi Yamada, Kuninori Kawabata, Shigemasa Ito
  • Publication number: 20060256638
    Abstract: A semiconductor memory device with low power consumption in driving control signals of shift registers. The device contains a plurality of memory cell arrays each composed of a predetermined number of rows of memory cells. One set of shift registers are coupled to each cell array, and the nth set of shift registers successively activate word line selection signals according to a given control signal, so that the corresponding word lines of the nth cell array will be refreshed. Also coupled to each cell array is a shift register controller. The nth shift register controller provides a control signal to the nth set of shift registers when the nth cell array is being refreshed. When the refresh of that cell array is finished, the nth shift register controller forwards the control signal to the (n+1)th set of shift registers, thus initiating refresh operation for the (n+1)th cell array.
    Type: Application
    Filed: July 14, 2006
    Publication date: November 16, 2006
    Inventors: Kaoru Mori, Katuhiro Mori, Shinichi Yamada, Kuninori Kawabata, Shigemasa Ito
  • Publication number: 20040184323
    Abstract: A semiconductor memory device with low power consumption in driving control signals of shift registers. The device contains a plurality of memory cell arrays each composed of a predetermined number of rows of memory cells. One set of shift registers are coupled to each cell array, and the nth set of shift registers successively activate word line selection signals according to a given control signal, so that the corresponding word lines of the nth cell array will be refreshed. Also coupled to each cell array is a shift register controller. The nth shift register controller provides a control signal to the nth set of shift registers when the nth cell array is being refreshed. When the refresh of that cell array is finished, the nth shift register controller forwards the control signal to the (n+1)th set of shift registers, thus initiating refresh operation for the (n+1)th cell array.
    Type: Application
    Filed: March 16, 2004
    Publication date: September 23, 2004
    Applicant: FUJITSU LIMITED
    Inventors: Kaoru Mori, Katuhiro Mori, Shinichi Yamada, Kuninori Kawabata, Shigemasa Ito