Patents by Inventor Syouhei Yamamoto

Syouhei Yamamoto 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: 7135849
    Abstract: An extremal voltage detector produces an output voltage from an operational amplifier having its non-inverting input terminal connected to a first node and its inverting input terminal connected to a second node. A number of identical metal-oxide-semiconductor field-effect transistors (MOSFETs) controlled by respective input voltages are connected in parallel between the first node and a first power supply terminal. Another identical MOSFET, controlled by the output voltage, is connected between the second node and the first power supply terminal. Alternatively, a plurality of identical MOSFET detection circuits, controlled by the input and output voltages, are connected in parallel between the first power supply node and the first and second nodes. A pair of constant-current circuits conduct equal currents from the first and second nodes to a second power-supply terminal.
    Type: Grant
    Filed: April 24, 2006
    Date of Patent: November 14, 2006
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Syouhei Yamamoto
  • Patent number: 5703518
    Abstract: An absolute value circuit according to the present invention has a configuration wherein a switch is connected directly to an output of an amplifier and an output terminal. Owing to this configuration, the absolute value circuit can be realized which is capable of providing full-wave rectification with less distortion.
    Type: Grant
    Filed: November 22, 1996
    Date of Patent: December 30, 1997
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Syouhei Yamamoto