Patents by Inventor Sao-Hung Lu

Sao-Hung Lu 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: 7741901
    Abstract: For charging a bootstrap capacitor in a voltage converter, a circuit is provided for wider bandwidth to eliminate the feedback stability issue and pin out for compensation circuit. A pair of transistors are connected in series between a power input and the bootstrap capacitor, the first transistor is switched synchronously with a low-side transistor of the voltage converter, and a comparator compares a feedback voltage drawn from a feedback node between the pair of transistors with a reference voltage, to control the second transistor to determine to charge the bootstrap capacitor.
    Type: Grant
    Filed: February 5, 2008
    Date of Patent: June 22, 2010
    Assignee: Richtek Technology Corp.
    Inventors: Sao-Hung Lu, Isaac Y. Chen
  • Publication number: 20080218141
    Abstract: For charging a bootstrap capacitor in a voltage converter, a circuit is provided for wider bandwidth to eliminate the feedback stability issue and pin out for compensation circuit. A pair of transistors are connected in series between a power input and the bootstrap capacitor, the first transistor is switched synchronously with a low-side transistor of the voltage converter, and a comparator compares a feedback voltage drawn from a feedback node between the pair of transistors with a reference voltage, to control the second transistor to determine to charge the bootstrap capacitor.
    Type: Application
    Filed: February 5, 2008
    Publication date: September 11, 2008
    Inventors: Sao-Hung Lu, Isaac Y. Chen
  • Patent number: 7106033
    Abstract: This invention relates to a quick-recovery low dropout linear regulator (LDO), which utilizes a current-detection circuit to detect the magnitude of the output current, and the output current compares with a reference current so as to dynamically adjust the bias-current of the 2nd stage amplifier such that the system remains stable even when the output current is high resulting from the damping ratio ? is still greater than 1. As a result, the output voltage can quickly recover stability from a large and sudden change of the output current.
    Type: Grant
    Filed: June 6, 2005
    Date of Patent: September 12, 2006
    Assignee: Sitronix Technology Corp.
    Inventors: Shen-Iuan Liu, Sao-Hung Lu