Patents by Inventor Yoshio Iioka

Yoshio Iioka 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: 6996661
    Abstract: A multiport memory has a plurality of RAMs and a port expansion unit electrically connected to access ports of the RAMs. The port expansion unit includes an input circuit which allows access control information for activating the RAMs in parallel every memory cycles to be collectively inputted thereto by a plurality of memory cycles, a timing generator which generates internal clock signals capable of serially prescribing each memory cycle plural times during one cycle of a clock signal (ck), and a logic circuit capable of sequentially supplying the access control information inputted to the input circuit to the plurality of RAMs in parallel in parts every serial memory cycles synchronized with the internal clock signals. The port expansion unit allows access to the access ports with the plurality of RAMs as a single multiport memory apparently.
    Type: Grant
    Filed: July 10, 2003
    Date of Patent: February 7, 2006
    Assignees: Renesas Technology Corp., Hitachi ULSI Systems Co., Ltd.
    Inventors: Masami Hasegawa, Yoichi Satoh, Yuuji Yanagisawa, Yoshio Iioka, Yoshimi Kitagawa, Makio Uchida
  • Publication number: 20040107307
    Abstract: A multiport memory has a plurality of RAMs and a port expansion unit electrically connected to access ports of the RAMs. The port expansion unit includes an input circuit which allows access control information for activating the RAMs in parallel every memory cycles to be collectively inputted thereto by a plurality of memory cycles, a timing generator which generates internal clock signals capable of serially prescribing each memory cycle plural times during one cycle of a clock signal (ck), and a logic circuit capable of sequentially supplying the access control information inputted to the input circuit to the plurality of RAMs in parallel in parts every serial memory cycles synchronized with the internal clock signals. The port expansion unit allows access to the access ports with the plurality of RAMs as a single multiport memory apparently.
    Type: Application
    Filed: July 10, 2003
    Publication date: June 3, 2004
    Applicants: Hitachi, Ltd., Hitachi ULSI Systems Co., Ltd.
    Inventors: Masami Hasegawa, Yoichi Satoh, Yuuji Yanagisawa, Yoshio Iioka, Yoshimi Kitagawa, Makio Uchida
  • Patent number: 6625686
    Abstract: A multiport memory has a plurality of RAMs and a port expansion unit electrically connected to access ports of the RAMs. The port expansion unit includes an input circuit which allows access control information for activating the RAMs in parallel every memory cycles to be collectively inputted thereto by a plurality of memory cycles, a timing generator which generates internal clock signals capable of serially prescribing each memory cycle plural times during one cycle of a clock signal (ck), and a logic circuit capable of sequentially supplying the access control information inputted to the input circuit to the plurality of RAMs in parallel in parts every serial memory cycles synchronized with the internal clock signals. The port expansion unit allows access to the access ports with the plurality of RAMs as a single multiport memory apparently.
    Type: Grant
    Filed: August 8, 2002
    Date of Patent: September 23, 2003
    Assignees: Hitachi, Ltd., Hitachi ULSI Systems, Co., Ltd.
    Inventors: Masami Hasegawa, Yoichi Satoh, Yuuji Yanagisawa, Yoshio Iioka, Yoshimi Kitagawa, Makio Uchida
  • Publication number: 20020194424
    Abstract: A multiport memory has a plurality of RAMs and a port expansion unit electrically connected to access ports of the RAMs. The port expansion unit includes an input circuit which allows access control information for activating the RAMs in parallel every memory cycles to be collectively inputted thereto by a plurality of memory cycles, a timing generator which generates internal clock signals capable of serially prescribing each memory cycle plural times during one cycle of a clock signal (ck), and a logic circuit capable of sequentially supplying the access control information inputted to the input circuit to the plurality of RAMs in parallel in parts every serial memory cycles synchronized with the internal clock signals. The port expansion unit allows access to the access ports with the plurality of RAMs as a single multiport memory apparently.
    Type: Application
    Filed: August 8, 2002
    Publication date: December 19, 2002
    Applicant: Hitachi, Ltd.
    Inventors: Masami Hasegawa, Yoichi Satoh, Yuuji Yanagisawa, Yoshio Iioka, Yoshimi Kitagawa, Makio Uchida
  • Patent number: 6480947
    Abstract: A multiport memory has a plurality of RAMs and a port expansion unit electrically connected to access ports of the RAMs. The port expansion unit includes an input circuit which allows access control information for activating the RAMs in parallel every memory cycles to be collectively inputted thereto by a plurality of memory cycles, a timing generator which generates internal clock signals capable of serially prescribing each memory cycle plural times during one cycle of a clock signal (ck), and a logic circuit capable of sequentially supplying the access control information inputted to the input circuit to the plurality of RAMs in parallel in parts every serial memory cycles synchronized with the internal clock signals. The port expansion unit allows access to the access ports with the plurality of RAMs as a single multiport memory apparently.
    Type: Grant
    Filed: July 15, 1999
    Date of Patent: November 12, 2002
    Assignees: Hitachi, Ltd., Hitachi Ulsi Systems Co. Ltd.
    Inventors: Masami Hasegawa, Yoichi Satoh, Yuuji Yanagisawa, Yoshio Iioka, Yoshimi Kitagawa, Makio Uchida
  • Patent number: 5317537
    Abstract: A multi-port memory device has a memory cell array including one or more memory blocks each of which has a plurality of memory cells arranged in rows and columns, and a plurality of dummy cells, with one dummy cell being provided for each row of memory cells in each of the memory blocks so that the dummy cells are connected with associated ones of the word lines extending in the row direction. The dummy cells are further connected with dummy cell bit lines extending in the column direction. Sense amplifiers are connected to receive outputs of those memory cells in the memory cell array which are selected in a memory cell selection operation and outputs of those dummy cells among the plurality of dummy cells which are selected in the memory cell selection operation for amplifying differences between the selected memory cell outputs and the selected dummy cell outputs. Precharging and shielding arrangements are also provided for improved operation.
    Type: Grant
    Filed: May 27, 1992
    Date of Patent: May 31, 1994
    Assignees: Hitachi, Ltd., Hitachi VLSI Engineering Corp.
    Inventors: Satoshi Shinagawa, Yoichi Sato, Masami Hasegawa, Yasushi Shimono, Masayuki Miyasaka, Takatoshi Tamura, Yoshio Iioka