Patents by Inventor Chang Duan

Chang Duan 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).

  • Publication number: 20090147419
    Abstract: An electronic device includes an integrated circuit, a power interface, and an interface circuit connected between the integrated circuit and the power interface for protecting the integrated circuit from being damaged by electrostatic discharge. The interface circuit includes a current limit unit connected between the power interface and the integrated circuit for limiting an electrostatic discharge current and an electrostatic protection unit connected to a common node of the power interface and the current limit unit for clamping a voltage of the common node to a predetermined value. A related integrated circuit is also provided.
    Type: Application
    Filed: June 27, 2008
    Publication date: June 11, 2009
    Applicants: HONG FU JIN PRECISION INDUSTRY (ShenZhen) CO., LTD., HON HAI PRECISION INDUSTRY CO., LTD.
    Inventors: CHUN-LUNG HUNG, TAO WANG, SHI-MING ZHANG, WANG-CHANG DUAN, WEN-MING CHEN, PEI LIU
  • Publication number: 20090134934
    Abstract: An electronic device includes a power interface for transmitting power, an integrated circuit capable of resetting, and a switch circuit. The switch circuit is connected to the power interface for transmitting the power to the integrated circuit after the integrated circuit is reset and stop transmitting the power to the integrated circuit if the integrated circuit is resetting.
    Type: Application
    Filed: July 7, 2008
    Publication date: May 28, 2009
    Applicants: HONG FU JIN PRECISION INDUSTRY (ShenZhen) CO., LTD., HON HAI PRECISION INDUSTRY CO., LTD.
    Inventors: Chun-Lung Hung, Wen-Ming Chen, Wang-Chang Duan, Tao Wang, Kun Huang, Shi-Ming Zhang
  • Publication number: 20090127935
    Abstract: A power supply system for an electronic device includes a first and a second connector, a switch, and a controller. The first connector is used for connecting to a first power source. The second connector is used for connecting to a second power source, wherein the second power source is rechargeable. The switch establishes a connection between the first connector and the second connector so as to allow the first power source to charge the second power source. The controller detects a presence of the first power source and the second power source, and controls the switch to periodically establish the connection at the absence of the second power source, and to continuously establish the connection at the presence of the second power source.
    Type: Application
    Filed: August 20, 2008
    Publication date: May 21, 2009
    Applicants: HONG FU JIN PRECISION INDUSTRY (ShenZhen) CO., LTD., HON HAI PRECISION INDUSTRY CO., LTD.
    Inventors: CHUN-LUNG HUNG, WANG-CHANG DUAN, WEN-MING CHEN, TAO WANG, SHI-MING ZHANG, PEI LIU
  • Publication number: 20090115511
    Abstract: An audio amplifier is provided. The audio amplifier includes an amplifier, a biasing circuit, and a time-delay circuit. The amplifier circuit is for amplifying audio signals. The biasing circuit is for providing a bias voltage to the amplifier circuit to actuate the amplifier circuit. The time-delay circuit is for receiving a pulse signal and delaying the bias voltage to avoid a sudden actuation of the amplifier circuit.
    Type: Application
    Filed: August 7, 2008
    Publication date: May 7, 2009
    Applicants: HONG FU JIN PRECISION INDUSTRY (ShenZhen) CO., LTD, HON HAI PRECISION INDUSTRY CO., LTD.
    Inventors: CHUN-LUNG HUNG, WEN-MING CHEN, JIE LIU, DE-AN ZHANG, WANG-CHANG DUAN, TAO WANG
  • Publication number: 20060107287
    Abstract: The present invention proposes a method of making use of Cell Broadcast to support MBMS transfer service announcement or service notification transfer. The method of transferring service announcement comprises the following steps: CBC commands UTRAN connected with it by a signaling message to send service announcement; UTRAN arranges the prescribed time of sending MBMS service announcement message, adds the brief description information to the schedule message and sends the schedule message; after receiving the schedule message, UE configures physical layer thereof to prepare for receiving MBMS service announcement message. UTARN sends MBMS service announcement message at the prescribed time.
    Type: Application
    Filed: August 14, 2003
    Publication date: May 18, 2006
    Inventors: Kook-Heui Lee, Soeng-Hun Kim, Sung-Ho Choi, Chang Duan, Detao Li