Patents by Inventor Junjie Zheng

Junjie Zheng 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: 7433211
    Abstract: A power converter delivers electrical power from an electrical power source to a load according to a plurality of operation modes, where at least one of the operation modes is a peak current switching mode. Under the peak current switching mode, a switch controller controls the switch in the power converter to be kept on until the current through the switch reaches a peak current value corresponding to a given phase of the input voltage signal to the power converter. The peak current values have a reference shape, which may be a trapezoidal. The power converter may have any topology, such as a flyback-type power converter or a boost-type power converter.
    Type: Grant
    Filed: June 28, 2004
    Date of Patent: October 7, 2008
    Assignee: iWatt Inc.
    Inventors: Arthur J. Collmeyer, Anatoly Shteynberg, Junjie Zheng, Paul F. King, Dickson T. Wong, Harry Rodriguez
  • Publication number: 20080112193
    Abstract: A primary side sensing power control system and method for constant current control that utilizes a relationship that involves the measured reset-time from the previous cycle to determine the primary side peak current and off-time for the next cycle. This control mechanism does not need the knowledge of input voltage or magnetizing inductance. Therefore, it removes the sensitivities of input voltage and magnetizing inductance to the output current limit. Furthermore, it uses a time measurement instead of a voltage measurement for the current calculation which in many cases is easier to perform.
    Type: Application
    Filed: May 7, 2007
    Publication date: May 15, 2008
    Applicant: iWatt Inc.
    Inventors: Liang Yan, Junjie Zheng, John Kesterson, Xiaoyan Wang, Hien Bui
  • Publication number: 20080067994
    Abstract: A modification of a control loop of a primary side sensing power control system that uses a different and unique relationship to accomplish the constant current control while attenuating the affects of a ripple voltage.
    Type: Application
    Filed: September 17, 2007
    Publication date: March 20, 2008
    Inventors: John Kesterson, Junjie Zheng
  • Patent number: 7161816
    Abstract: A power converter delivers electrical power from an electrical power source to a load according to a plurality of operation modes corresponding to different levels of input voltage or output current. The power converter comprises a power stage for delivering the electrical power from the power source to the load, a switch in the power stage that electrically couples or decouples the load to the power source, and a switch controller coupled to the switch for controlling the on-times and off-times of the switch according to the plurality of operation modes. Each of the operation modes correspond to associated ranges of at least one of an input voltage to the power converter and an output current from the power converter, where the associated ranges are different for each of the operation modes.
    Type: Grant
    Filed: August 19, 2005
    Date of Patent: January 9, 2007
    Assignee: iWatt Inc.
    Inventors: Anatoly Shteynberg, Junjie Zheng, Harry Rodriguez, Mark D. Telefus, Dongsheng Zhou, Arthur J. Collmeyer
  • Publication number: 20060002155
    Abstract: A power converter delivers electrical power from an electrical power source to a load according to a plurality of operation modes corresponding to different levels of input voltage or output current. The power converter comprises a power stage for delivering the electrical power from the power source to the load, a switch in the power stage that electrically couples or decouples the load to the power source, and a switch controller coupled to the switch for controlling the on-times and off-times of the switch according to the plurality of operation modes. Each of the operation modes correspond to associated ranges of at least one of an input voltage to the power converter and an output current from the power converter, where the associated ranges are different for each of the operation modes.
    Type: Application
    Filed: August 19, 2005
    Publication date: January 5, 2006
    Inventors: Anatoly Shteynberg, Junjie Zheng, Harry Rodriguez, Mark Telefus, Dongsheng Zhou, Arthur Collmeyer
  • Patent number: 6972969
    Abstract: A primary side sensing power control system and method that controls the current limit such that it is maintained within a small range for any acceptable input voltages and causes the output voltage of a PWM controller to drop as the output load increases when the current limit is reached.
    Type: Grant
    Filed: August 19, 2004
    Date of Patent: December 6, 2005
    Assignee: iWatt, Inc.
    Inventors: Anatoly Shteynberg, Junjie Zheng, Harry Rodriguez, Mark D. Telefus, Dongsheng Zhou
  • Patent number: 6944034
    Abstract: A power converter delivers electrical power from an electrical power source to a load according to a plurality of operation modes corresponding to different levels of input voltage or output current. The power converter comprises a power stage for delivering the electrical power from the power source to the load, a switch in the power stage that electrically couples or decouples the load to the power source, and a switch controller coupled to the switch for controlling the on-times and off-times of the switch according to the plurality of operation modes. Each of the operation modes correspond to associated ranges of at least one of an input voltage to the power converter and an output current from the power converter, where the associated ranges are different for each of the operation modes.
    Type: Grant
    Filed: June 30, 2003
    Date of Patent: September 13, 2005
    Assignee: iWatt Inc.
    Inventors: Anatoly Shteynberg, Junjie Zheng, Harry Rodriguez, Mark D. Telefus, Dongsheng Zhou, Arthur J. Collmeyer