Patents by Inventor Li Fang Guo

Li Fang Guo 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).

  • Clamp protection circuit and a PFC control circuit employing such clamp protection circuit
    Patent number: 8045308
    Abstract: The present invention relates to clamp protection circuit and a PFC control circuit employing such clamp protection circuit. Said clamp protection circuit comprises a high voltage isolation module used for receiving power from a high voltage power supply; a voltage clamp module used for receiving an output low voltage from the high voltage isolation module and realizing a clamp protection; and a low voltage bias module used for providing bias voltage to the high voltage isolation module and the voltage clamp module. By employing the clamp protection circuit, the precision of the clamp voltage is improved, the design is simplified and the silicon area is reduced. Meanwhile, the transient response is enhanced.
    Type: Grant
    Filed: April 2, 2009
    Date of Patent: October 25, 2011
    Assignee: Evergreen Micro Devices Co., Ltd.
    Inventors: Run Qin Tan, Li Fang Guo, Matthew Man Ho Ku
  • CLAMP PROTECTION CIRCUIT AND A PFC CONTROL CIRCUIT EMPLOYING SUCH CLAMP PROTECTION CIRCUIT
    Publication number: 20100253410
    Abstract: The present invention relates to clamp protection circuit and a PFC control circuit employing such clamp protection circuit. Said clamp protection circuit comprises a high voltage isolation module used for receiving power from a high voltage power supply; a voltage clamp module used for receiving an output low voltage from the high voltage isolation module and realizing a clamp protection; and a low voltage bias module used for providing bias voltage to the high voltage isolation module and the voltage clamp module. By employing the clamp protection circuit, the precision of the clamp voltage is improved, the design is simplified and the silicon area is reduced. Meanwhile, the transient response is enhanced.
    Type: Application
    Filed: April 2, 2009
    Publication date: October 7, 2010
    Applicant: EVERGREEN MICRO DEVICES CO., LTD.
    Inventors: Run Qin Tan, Li Fang Guo, Matthew Man Ho Ku