Patents by Inventor Mitsuya Kawata

Mitsuya Kawata 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: 6936889
    Abstract: A semiconductor device having at least three independently accessible memories, with at least one of the memories having a different memory capacity than the others. Separate selection signals are provided to the memories so that they can be independently activated. This allows the memories to be separately tested. When testing the semiconductor device, the memories are tested serially, except for the memory with the largest capacity, since this memory also has the longest test time. The memory with the longest test time is tested in parallel with the serially tested memories. This reduces the current that must be supplied by a test device to the semiconductor device during testing.
    Type: Grant
    Filed: April 15, 2004
    Date of Patent: August 30, 2005
    Assignee: Fujitsu Limited
    Inventors: Makoto Koga, Kunihiko Gotoh, Kenichi Matsumaru, Mitsuya Kawata
  • Publication number: 20040190355
    Abstract: A semiconductor device having at least three independently accessible memories, with at least one of the memories having a different memory capacity than the others. Separate selection signals are provided to the memories so that they can be independently activated. This allows the memories to be separately tested. When testing the semiconductor device, the memories are tested serially, except for the memory with the largest capacity, since this memory also has the longest test time. The memory with the longest test time is tested in parallel with the serially tested memories. This reduces the current that must be supplied by a test device to the semiconductor device during testing.
    Type: Application
    Filed: April 15, 2004
    Publication date: September 30, 2004
    Applicant: FUJITSU LIMITED
    Inventors: Makoto Koga, Kunihiko Gotoh, Kenichi Matsumaru, Mitsuya Kawata
  • Patent number: 6740929
    Abstract: A semiconductor device having at least three independently accessible memories, with at least one of the memories having a different memory capacity than the others. Separate selection signals are provided to the memories so that they can be independently activated. This allows the memories to be separately tested. When testing the semiconductor device, the memories are tested serially, except for the memory with the largest capacity, since this memory also has the longest test time. The memory with the longest test time is tested in parallel with the serially tested memories. This reduces the current that must be supplied by a test device to the semiconductor device during testing.
    Type: Grant
    Filed: December 17, 2002
    Date of Patent: May 25, 2004
    Assignee: Fujitsu Limited
    Inventors: Makoto Koga, Kunihiko Gotoh, Kenichi Matsumaru, Mitsuya Kawata
  • Publication number: 20030067016
    Abstract: A semiconductor device having at least three independently accessible memories, with at least one of the memories having a different memory capacity than the others. Separate selection signals are provided to the memories so that they can be independently activated. This allows the memories to be separately tested. When testing the semiconductor device, the memories are tested serially, except for the memory with the largest capacity, since this memory also has the longest test time. The memory with the longest test time is tested in parallel with the serially tested memories. This reduces the current that must be supplied by a test device to the semiconductor device during testing.
    Type: Application
    Filed: December 17, 2002
    Publication date: April 10, 2003
    Applicant: FUJITSU LIMITED
    Inventors: Makoto Koga, Kunihiko Gotoh, Kenichi Matsumaru, Mitsuya Kawata
  • Patent number: 6528817
    Abstract: A semiconductor device having at least three independently accessible memories, with at least one of the memories having a different memory capacity than the others. Separate selection signals are provided to the memories so that they can be independently activated. This allows the memories to be separately tested. When testing the semiconductor device, the memories are tested serially, except for the memory with the largest capacity, since this memory also has the longest test time. The memory with the longest test time is tested in parallel with the serially tested memories. This reduces the current that must be supplied by a test device to the semiconductor device during testing.
    Type: Grant
    Filed: July 26, 2000
    Date of Patent: March 4, 2003
    Assignee: Fujitsu Limited
    Inventors: Makoto Koga, Kunihiko Gotoh, Kenichi Matsumaru, Mitsuya Kawata
  • Patent number: 4825414
    Abstract: A semiconductor integrated circuit device has a normal mode and a test mode for testing a memory thereof, and comprises input/output buffer parts having input/output terminals, at least one gate array, at least one memory, a first interconnection for coupling the input/output buffer parts, the gate array and the memory and routed depending on a logic operation to be carried out by the semiconductor integrated circuit, and a second interconnection for coupling the input/output buffer parts, the gate array and the memory, where the second interconnection is fixed regardless of the logic operation to be carried out by the semiconductor integrated circuit.
    Type: Grant
    Filed: June 24, 1988
    Date of Patent: April 25, 1989
    Assignee: Fujitsu Limited
    Inventor: Mitsuya Kawata
  • Patent number: 4791320
    Abstract: A compound transistor type inverter, i.e., comprised of MIS and bipolar transistors, including, at the output stage thereof, an npn transistor operative to charge a load. The npn transistor can be quickly cut OFF by an additional transistor, and simultaneously, the additional transistor is operative to attain a quick discharge from the load. Still another additional transistor is employed, in a case where the inverter includes a pnp transistor, other than the npn transistor, at a ground side, which another additional transistor is operative to bypass the collector and emitter of the pnp transistor.
    Type: Grant
    Filed: August 18, 1986
    Date of Patent: December 13, 1988
    Assignee: Fujitsu Limited
    Inventors: Mitsuya Kawata, Tetsu Tanizawa