Patents by Inventor James S. Zeng

James S. Zeng 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: 6995995
    Abstract: A power control circuit is provided containing a switch array, which includes segmented switches, a flying capacitor, an output voltage terminal, a feedback loop, and a digital voltage regulator block. The digital voltage regulator block includes an A/D converter, an encoder, an add-subtractor, and a gate logic. These power control circuits do not include pass transistors. A method is also provided, where the charge pumps of the power control circuit are operated in two-phase cycles including a charging phase and a pumping phase. The power control circuit is controlled in both of these phases, thereby reducing the ripple of the output voltage.
    Type: Grant
    Filed: December 3, 2003
    Date of Patent: February 7, 2006
    Assignee: Fairchild Semiconductor Corporation
    Inventors: James S. Zeng, Sridhar Kotikalapoodi, Lajos Burgyan
  • Patent number: 6920055
    Abstract: A charge pumping system capable of a forward operation mode and a reverse operation mode is provided. In forward operation mode the charge pumping system can step-up an input voltage at a ratio of ½:1 and can step-down the input voltage at a ratio of n:m where n and m are both integer values and n is equal to or greater than m. In reverse operation mode the charge pumping system can step-down the input voltage at a ratio of 1:½ and 1:1 and can step-up the input voltage at a ratio of p:q where p and q are both integer values and p is less than q.
    Type: Grant
    Filed: October 3, 2003
    Date of Patent: July 19, 2005
    Assignee: Fairchild Semiconductor Corporation
    Inventors: James S. Zeng, Lajos Burgyan, Rendon A. Holloway
  • Patent number: 6657875
    Abstract: A charge pumping system capable of a forward operation mode and a reverse operation mode is provided. In forward operation mode the charge pumping system can step-up an input voltage at a ratio of ½:1 and can step-down the input voltage at a ratio of at east one of 1:1, 3:2, 2:1 and 3:1. In reverse operation mode the charge pumping system can step-down the input voltage at a ratio of 1:½and 1:1 and can step-up the input voltage at a ratio of at least one of 2:3, 1:2 and 1:3.
    Type: Grant
    Filed: July 16, 2002
    Date of Patent: December 2, 2003
    Assignee: Fairchild Semiconductor Corporation
    Inventors: James S. Zeng, Lajos Burgyan, Rendon A. Holloway