Patents by Inventor Thai Quoc Ngo

Thai Quoc Ngo 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: 6667893
    Abstract: A power converter controller and a method for controlling a power converter are provided. The power converter includes first and second power transformers, each having first and second primary windings and a secondary winding; and first and second switches that alternately couple primary windings of the first and second power transformers to an input power source. The power converter controller receives a feedback signal, such as a DC power output voltage from the power converter. A voltage controlled oscillator responsive to the feedback signal provides a variable frequency signal. A phase shift controller coupled to the voltage controlled oscillator provides a variable phase shifted signal responsive to the variable frequency signal. Gate drive signals are decoded using the variable frequency signal and variable phase shifted signal for driving first and second switches of the power converter.
    Type: Grant
    Filed: April 25, 2002
    Date of Patent: December 23, 2003
    Assignee: International Business Machines Corporation
    Inventors: Timothy Charles Daun-Lindberg, Richard John Fishbune, Thai Quoc Ngo, Scott Douglas Strand
  • Publication number: 20030202365
    Abstract: A power converter controller and a method for controlling a power converter are provided. The power converter includes first and second power transformers, each having first and second primary windings and a secondary winding; and first and second switches that alternately couple primary windings of the first and second power transformers to an input power source. The power converter controller receives a feedback signal, such as a DC power output voltage from the power converter. A voltage controlled oscillator responsive to the feedback signal provides a variable frequency signal. A phase shift controller coupled to the voltage controlled oscillator provides a variable phase shifted signal responsive to the variable frequency signal. Gate drive signals are decoded using the variable frequency signal and variable phase shifted signal for driving first and second switches of the power converter.
    Type: Application
    Filed: April 25, 2002
    Publication date: October 30, 2003
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Timothy Charles Daun-Lindberg, Richard John Fishbune, Thai Quoc Ngo, Scott Douglas Strand
  • Patent number: 6442052
    Abstract: A high efficiency power converter and method of operation thereof. The high efficiency power converter includes a preregulator circuit that provides a regulated intermediate DC voltage to a low impedance output stage. The low impedance output stage includes first and second power transformers, where each of the power transformers has first and second primary windings of opposite polarity and a secondary winding. The low impedance output stage also includes first and second switches that alternatively couple the first primary windings of the first and second power transformers, respectively, to the regulated intermediate DC voltage. The low impedance output stage further includes first and second coupling capacitors that couple the second primary windings of the first and second power transformers to the second and first switches, respectively, and are utilized to reset the first and second power transformers with minimum losses.
    Type: Grant
    Filed: August 30, 2001
    Date of Patent: August 27, 2002
    Assignee: International Business Machines Corporation
    Inventors: William Hemena, Thai Quoc Ngo, Scott Douglas Strand
  • Patent number: 6400582
    Abstract: A dual forward power converter and method of operation thereof. The dual forward power converter includes first and second power transformers, where each of the power transformers has first and second primary windings of opposite polarity and a secondary winding. The dual forward power converter also includes first and second switches that alternatively couple the first primary windings of the first and second power transformers, respectively, to a source of input power. The first and second switches, in an advantageous embodiment, are Field Effect Transistors (FETs) and are driven in a complementary manner with substantially 50% duty cycles. The dual forward power converter further includes first and second coupling capacitors that couple the second primary windings of the first and second power transformers to the second and first switches, respectively, and are utilized to reset the first and second power transformers with minimum losses.
    Type: Grant
    Filed: November 21, 2000
    Date of Patent: June 4, 2002
    Assignee: International Business Machines Corporation
    Inventors: William Hemena, Thai Quoc Ngo, Scott Douglas Strand