Patents by Inventor Dung A. Tran

Dung A. Tran 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: 7391165
    Abstract: A discharge lamp lighting control device (100) having a DC power converter, a power factor improving power converter (1), a polarity reversing circuit (2), a starter circuit (3), and a controller (4). The power factor improving power converter 1 includes a switching device S, a power factor improver, and a power converter. The power factor improver operates to smooth a rectified voltage by storing energy in a first inductive device L1 and by discharging energy from a second inductive device L2, in which the first and second inductive devices are magnetically coupled together. The storing and discharging is performed by turning ON and OFF the switching device S. A predetermined DC voltage is converted by energy stored and discharged by a third inductive device L3 in response to the turning ON and OFF of the switching device S.
    Type: Grant
    Filed: April 22, 2004
    Date of Patent: June 24, 2008
    Assignees: Matsushita Electric Works, Ltd., Virginia Tech Intellectual Properties, Inc.
    Inventors: Fred C. Lee, Jinghai Zhou, Yan Jiang, Masanao Okawa, Dung A. Tran, Hiroyasu Eriguchi
  • Patent number: 6020743
    Abstract: A technique for detecting failed batteries while the battery is attached to one or more electronic devices and is receiving a float charge is disclosed. The float voltage minimizes the normal voltage differences between battery cells. The technique employs a ratio comparative analysis of cell voltages of a battery provided across the terminals of the battery. Application of the ratio comparative analysis in assessing the condition of a battery assumes an equal voltage drop across each battery cell such that the cells are modeled as a series of resisters with respect to the float voltage. Such equal voltage drop enables a comparative ratio analysis of the voltage across each of the two portions of the battery's cell stack to the voltage across the entire battery. The comparative ratio analysis determines a voltage threshold that identifies whether a battery has a shorted or open cell.
    Type: Grant
    Filed: October 21, 1997
    Date of Patent: February 1, 2000
    Assignee: Compaq Computer Corporation
    Inventors: Larry D. Reeves, Kan-Chiu Seto, Dung A. Tran