Patents by Inventor Ayako Kakuda

Ayako Kakuda 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: 7342826
    Abstract: The read speed of an on-chip nonvolatile memory enabling electric rewrite is increased. The nonvolatile memory has a hierarchal bit line structure having first bit lines specific to each of a plurality of memory arrays, a second bit line shared between the plurality of memory arrays, a first selector circuit selecting the first bit line for each of the memory arrays to connect the selected first bit line to the second bit line, and a sense amp arranged between the output of the first selector circuit and the second bit line. The hierarchal bit line structure having the divided memory arrays can reduce the input load capacity of the sense amp.
    Type: Grant
    Filed: March 2, 2007
    Date of Patent: March 11, 2008
    Assignee: Renesas Technology Corp.
    Inventors: Masamichi Fujito, Yutaka Shinagawa, Kazufumi Suzukawa, Ayako Kakuda, Akira Kato, Toshihiro Tanaka
  • Publication number: 20070153618
    Abstract: The read speed of an on-chip nonvolatile memory enabling electric rewrite is increased. The nonvolatile memory has a hierarchal bit line structure having first bit lines specific to each of a plurality of memory arrays, a second bit line shared between the plurality of memory arrays, a first selector circuit selecting the first bit line for each of the memory arrays to connect the selected first bit line to the second bit line, and a sense amp arranged between the output of the first selector circuit and the second bit line. The hierarchal bit line structure having the divided memory arrays can reduce the input load capacity of the sense amp.
    Type: Application
    Filed: March 2, 2007
    Publication date: July 5, 2007
    Inventors: Masamichi Fujito, Yutaka Shinagawa, Kazufumi Suzukawa, Ayako Kakuda, Akira Kato, Toshihiro Tanaka
  • Patent number: 7190615
    Abstract: The read speed of an on-chip nonvolatile memory enabling electric rewrite is increased. The nonvolatile memory has a hierarchal bit line structure having first bit lines specific to each of a plurality of memory arrays, a second bit line shared between the plurality of memory arrays, a first selector circuit selecting the first bit line for each of the memory arrays to connect the selected first bit line to the second bit line, and a sense amp arranged between the output of the first selector circuit and the second bit line. The hierarchal bit line structure having the divided memory arrays can reduce the input load capacity of the sense amp.
    Type: Grant
    Filed: March 29, 2004
    Date of Patent: March 13, 2007
    Assignee: Renesas Technology Corp.
    Inventors: Masamichi Fujito, Yutaka Shinagawa, Kazufumi Suzukawa, Ayako Kakuda, Akira Kato, Toshihiro Tanaka
  • Publication number: 20070040595
    Abstract: A delay circuit includes a constant current source, a delay stage, and a compensating circuit. The delay circuit may compensate for a variation in a delay characteristic of the delay stage due to a variation in temperature, supply voltage and/or process.
    Type: Application
    Filed: October 26, 2006
    Publication date: February 22, 2007
    Inventors: Ayako Kakuda, Masamichi Fujito
  • Patent number: 7148732
    Abstract: A delay circuit includes a constant current source, a delay stage, and a compensating circuit. The delay circuit may compensate for a variation in a delay characteristic of the delay stage due to a variation in temperature, supply voltage and/or process.
    Type: Grant
    Filed: October 6, 2004
    Date of Patent: December 12, 2006
    Assignee: Renesas Technology Corp.
    Inventors: Ayako Kakuda, Masamichi Fujito
  • Publication number: 20050077943
    Abstract: A delay circuit comprises a constant current source, a delay stage in which an operation delay time of an output relative to an input is determined depending on a constant current produced by the constant current source, and a compensating circuit which compensates for a variation in delay characteristic of the delay stage due to a variation in temperature, a variation in power supply voltage and process variations in the opposite direction. When on resistance and threshold voltage characteristics of the compensating circuit and delay stage vary under the influence of the variations in temperature and power supply voltage or the like, a current (Id) changes following it but a current (Ip) changes so as to cancel it. As a result, the delay stage changes in its delay characteristic such that the influences such as the variations in temperature and power supply voltages are canceled out, and suppresses a variation in delay time.
    Type: Application
    Filed: October 6, 2004
    Publication date: April 14, 2005
    Inventors: Ayako Kakuda, Masamichi Fujito
  • Publication number: 20040202020
    Abstract: The read speed of an on-chip nonvolatile memory enabling electric rewrite is increased. The nonvolatile memory has a hierarchal bit line structure having first bit lines specific to each of a plurality of memory arrays, a second bit line shared between the plurality of memory arrays, a first selector circuit selecting the first bit line for each of the memory arrays to connect the selected first bit line to the second bit line, and a sense amp arranged between the output of the first selector circuit and the second bit line. The hierarchal bit line structure having the divided memory arrays can reduce the input load capacity of the sense amp.
    Type: Application
    Filed: March 29, 2004
    Publication date: October 14, 2004
    Applicant: Renesas Technology Corp.
    Inventors: Masamichi Fujito, Yutaka Shinagawa, Kazufumi Suzukawa, Ayako Kakuda, Akira Kato, Toshihiro Tanaka