Patents by Inventor Tim Cheung Leung

Tim Cheung Leung 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: 9621056
    Abstract: A method of controlling a phase-shift full-bridge (PSFB) converter in a light load operation is provided to switch control modes of the PSFB converter by detecting magnetizing current of a transformer thereof. The method includes following steps: First, the PSFB converter is operated in an extended PSFB control mode when the magnetizing current is larger. Afterward, the PSFB converter is operated in a modified PSFB control mode when the magnetizing current is gradually reduced and electric charges transported by the residual magnetizing current near to or less than a half of the DC input voltage. Finally, the optimal degree of soft switching of the PSFB converter is implemented when the PSFB converter is operated at the modified PSFB control mode. Accordingly, it is to improve overall efficiency, reduce switching losses, and achieve electromagnetic compatibility.
    Type: Grant
    Filed: December 18, 2015
    Date of Patent: April 11, 2017
    Assignee: Chicony Power Technology Co., Ltd.
    Inventors: Zhen-Yuan Wu, Tim-Cheung Leung
  • Publication number: 20160149498
    Abstract: A method of controlling a phase-shift full-bridge (PSFB) converter in a light load operation is provided to switch control modes of the PSFB converter by detecting magnetizing current of a transformer thereof. The method includes following steps: First, the PSFB converter is operated in an extended PSFB control mode when the magnetizing current is larger. Afterward, the PSFB converter is operated in a modified PSFB control mode when the magnetizing current is gradually reduced and electric charges transported by the residual magnetizing current near to or less than a half of the DC input voltage. Finally, the optimal degree of soft switching of the PSFB converter is implemented when the PSFB converter is operated at the modified PSFB control mode. Accordingly, it is to improve overall efficiency, reduce switching losses, and achieve electromagnetic compatibility.
    Type: Application
    Filed: December 18, 2015
    Publication date: May 26, 2016
    Inventors: Zhen-Yuan WU, Tim-Cheung LEUNG
  • Patent number: 9252672
    Abstract: A method of controlling a phase-shift full-bridge (PSFB) converter in a light load operation is provided to switch control modes of the PSFB converter by detecting magnetizing current of a transformer thereof. The method includes following steps: First, the PSFB converter is operated in an extended PSFB control mode when the magnetizing current is larger. Afterward, the PSFB converter is operated in a modified PSFB control mode when the magnetizing current is gradually reduced and electric charges transported by the residual magnetizing current near to or less than a half of the DC input voltage. Finally, the optimal degree of soft switching of the PSFB converter is implemented when the PSFB converter is operated at the modified PSFB control mode. Accordingly, it is to improve overall efficiency, reduce switching losses, and achieve electromagnetic compatibility.
    Type: Grant
    Filed: October 4, 2013
    Date of Patent: February 2, 2016
    Assignee: CHICONY POWER TECHNOLOGY CO., LTD.
    Inventors: Zhen-Yuan Wu, Tim-Cheung Leung
  • Publication number: 20150098250
    Abstract: A method of controlling a phase-shift full-bridge (PSFB) converter in a light load operation is provided to switch control modes of the PSFB converter by detecting magnetizing current of a transformer thereof. The method includes following steps: First, the PSFB converter is operated in an extended PSFB control mode when the magnetizing current is larger. Afterward, the PSFB converter is operated in a modified PSFB control mode when the magnetizing current is gradually reduced and electric charges transported by the residual magnetizing current near to or less than a half of the DC input voltage. Finally, the optimal degree of soft switching of the PSFB converter is implemented when the PSFB converter is operated at the modified PSFB control mode. Accordingly, it is to improve overall efficiency, reduce switching losses, and achieve electromagnetic compatibility.
    Type: Application
    Filed: October 4, 2013
    Publication date: April 9, 2015
    Applicant: Chicony Power Technology Co., Ltd.
    Inventors: Zhen-Yuan WU, Tim-Cheung LEUNG
  • Publication number: 20140369078
    Abstract: A bridge converter with a snubber circuit is applied to a power apparatus and a load apparatus. The bridge converter includes a transformer, a first diode, a secondary side first switch unit, a first capacitor, a second diode, a second capacitor, a secondary side second switch unit, a direct current to direct current conversion unit, a third capacitor and a resistor. The transformer includes a primary side winding, a first secondary side winding and a second secondary side winding.
    Type: Application
    Filed: June 13, 2014
    Publication date: December 18, 2014
    Inventors: Zhen-Yuan WU, Tim-Cheung LEUNG
  • Patent number: 8861237
    Abstract: A power supply apparatus mainly includes a secondary side controller, a digital isolator, a plurality of isolation sensing units, and a driving unit. The secondary side controller is configured to isolatedly measure voltages and currents, and is configured to isolatedly control the driving unit. The power supply apparatus includes a controller only, i.e. the secondary side controller 114. Therefore, the power consumption is lower, and the cost is lower. Only one controller is required to update software. There is no communication delay problem between two controllers.
    Type: Grant
    Filed: January 24, 2013
    Date of Patent: October 14, 2014
    Assignee: Chicony Power Technology Co., Ltd.
    Inventors: Zhen-Yuan Wu, Tim-Cheung Leung
  • Publication number: 20140204639
    Abstract: A power supply apparatus mainly includes a secondary side controller, a digital isolator, a plurality of isolation sensing units, and a driving unit. The secondary side controller is configured to isolatedly measure voltages and currents, and is configured to isolatedly control the driving unit. The power supply apparatus includes a controller only, i.e. the secondary side controller 114. Therefore, the power consumption is lower, and the cost is lower. Only one controller is required to update software. There is no communication delay problem between two controllers.
    Type: Application
    Filed: January 24, 2013
    Publication date: July 24, 2014
    Applicant: CHICONY POWER TECHNOLOGY CO., LTD.
    Inventors: Zhen-Yuan WU, Tim-Cheung LEUNG
  • Patent number: 7542309
    Abstract: A voltage stabilizer circuit of forward converter is disclosed to include a transformer, a first switch, a rectifier, an error amplifier, a control circuit, and a driving circuit. The control circuit outputs a regulation signal that controls turn-on time of the first switch, keeping the output of the load voltage at a stable level.
    Type: Grant
    Filed: November 21, 2006
    Date of Patent: June 2, 2009
    Assignee: Hipro Electronics Co., Ltd.
    Inventor: Tim Cheung Leung
  • Publication number: 20080049454
    Abstract: A voltage stabilizer circuit of forward converter is disclosed to include a transformer, a first switch, a rectifier, an error amplifier, a control circuit, and a driving circuit. The control circuit outputs a regulation signal that controls turn-on time of the first switch, keeping the output of the load voltage at a stable level.
    Type: Application
    Filed: November 21, 2006
    Publication date: February 28, 2008
    Inventor: Tim Cheung Leung