Patents by Inventor Hidetada Fukunaka

Hidetada Fukunaka 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: 6185481
    Abstract: A semiconductor device provided with a first cooling fan and heat-radiating fins is mounted on a board, and there is provided a second cooling fan for supplying cooling air to the board, such that a flow passage is formed for directing the cooling air, supplied from the second cooling fan, toward the board through the first cooling fan.
    Type: Grant
    Filed: November 28, 1997
    Date of Patent: February 6, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Yoshihiro Kondou, Tadakatsu Nakajima, Shigeo Ohashi, Susumu Iwai, Masayoshi Miyazaki, Shoohei Fuse, Kazuo Morita, Hidetada Fukunaka
  • Patent number: 5321666
    Abstract: A control circuit of a memory system including a dynamic random access memory may include a first integrated circuit formed on a common substrate. The first integrated circuit may include a circuit responsive to an external memory access request signal for generating a control signal for controlling an operation timing of the dynamic random access memory to supply the control signal to the dynamic random access memory and a circuit for generating an address signal for specifying an address of the dynamic random access memory to be accessed to supply the address signal to the dynamic random access memory. A second integrated circuit includes a read/write circuit for reading data from the dynamic random access memory and for writing data in the dynamic random access memory.
    Type: Grant
    Filed: June 17, 1991
    Date of Patent: June 14, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Hidetada Fukunaka, Akira Ishiyama
  • Patent number: 5109382
    Abstract: Method and apparatus for testing a memory mounted on an information processing system which includes a processor and at least one memory device. The memory device has a built-in memory test capability. In testing the memory mounted on the system, a test using the built-in test capability is combined with an additional test using a normal write/read operation of the memory performed by the processor unit. While the test using the built-in test capability is performed over the entire memory addresses, the additional test is performed with limited addresses.
    Type: Grant
    Filed: November 21, 1989
    Date of Patent: April 28, 1992
    Assignee: Hitachi, Ltd.
    Inventor: Hidetada Fukunaka
  • Patent number: 4779232
    Abstract: In a partial write control apparatus for a memory having a high speed operation mode such as a nibble mode or a page mode, when a partial write request for a plurality of words including those which require partial write is received, a memory control signal generator causes the memory to read successively all the words requiring partial write in a single high speed operation mode read cycle. A merging circuit merges those portions of the read-out words which need no alteration with write data and forms a group of updated complete words. Then, the memory control signal generator causes the memory to write successively these words in a single high speed operation mode write cycle.
    Type: Grant
    Filed: May 20, 1987
    Date of Patent: October 18, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Hidetada Fukunaka, Koichi Ikeda
  • Patent number: RE35978
    Abstract: A control circuit of a memory system including a dynamic random access memory may include a first integrated circuit formed on a common substrate. The first integrated circuit may include a circuit responsive to an external memory access request signal for generating a control signal for controlling an operation timing of the dynamic random access memory to supply the control signal to the dynamic random access memory and a circuit for generating an address signal for specifying an address of the dynamic random access memory to be accessed to supply the address signal to the dynamic random access memory. A second integrated circuit includes a read/write circuit for reading data from the dynamic random access memory and for writing data in the dynamic random access memory.
    Type: Grant
    Filed: June 12, 1996
    Date of Patent: December 1, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Hidetada Fukunaka, Akira Ishiyama