Patents by Inventor Fong-Lieh Liang

Fong-Lieh Liang 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).

  • Fast frequency locking method and architecture realized by employing adaptive asymmetric charge-pump current mechanism
    Patent number: 6894570
    Abstract: The present invention is related to a fast frequency locking method and architecture realized by employing adaptive asymmetric charge-pump current mechanism, whose circuit is composed of elements such as: a pair of frequency-dependent main current sources, a pair of (rising, descending) frequency-dependent assistant current sources, a digital control circuit, a voltage controlled oscillator, an impedance, a sampling frequency sampled from output frequency of the voltage controlled oscillator, a fixed reference frequency and a phase detector, etc. The difference between the present invention and traditional charge-pump circuit is that the present invention had added at least one pair of frequency-dependent assistant current sources.
    Type: Grant
    Filed: August 13, 2003
    Date of Patent: May 17, 2005
    Assignee: Holtek Semiconductor Inc.
    Inventor: Fong-Lieh Liang
  • Fast frequency locking method and architecture realized by employing adaptive asymmetric charge-pump current mechanism
    Publication number: 20040189402
    Abstract: The present invention is related to a fast frequency locking method and architecture realized by employing adaptive asymmetric charge-pump current mechanism, whose circuit is composed of elements such as: a pair of frequency-dependent main current sources, a pair of (rising, descending) frequency-dependent assistant current sources, a digital control circuit, a voltage controlled oscillator, an impedance, a sampling frequency sampled from output frequency of the voltage controlled oscillator, a fixed reference frequency and a phase detector, etc. The difference between the present invention and traditional charge-pump circuit is that the present invention had added at least one pair of frequency-dependent assistant current sources.
    Type: Application
    Filed: August 13, 2003
    Publication date: September 30, 2004
    Applicant: Holtek Semiconductor Inc.
    Inventor: Fong-Lieh Liang