Patents by Inventor Tadashi Yukawa

Tadashi Yukawa 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).

  • Switching power supply and method of controlling voltage induced across secondary winding of transformer
    Patent number: 6137698
    Abstract: A switching power supply has a secondary rectifying circuit including two MOS transistors which can operate in a third quadrant for use as low-loss rectifying devices. While the MOS transistors are operating in the third quadrant, the application of a gate voltage to the MOS transistors is forcibly stopped to turn off the MOS transistors. Periods in which the MOS transistors operate in the third quadrant are prevented from overlapping each other. The periods in which the MOS transistors operate in the third quadrant may be established by an ON timer, and the periods in which the MOS transistors remain de-energized may be established by an OFF timer.
    Type: Grant
    Filed: September 29, 1998
    Date of Patent: October 24, 2000
    Assignee: Shindengen Electric Manufacturing Co., Ltd.
    Inventors: Tadashi Yukawa, Nobuhiro Tada