Patents by Inventor Sum Chan

Sum Chan 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: 4871931
    Abstract: An improved logic circuit is disclosed, of the type in which one or more input signals, generated by one or more input signal generator circuits, are referenced to a threshold voltage, determined by a threshold voltage generator circuit, to determine whether said one or more input signals are in a high or low state. In this improved logic circuit, the time constants of the input signal generator circuits are matched with those of the threshold voltage generator circuit so that any power supply perturbations commonly applied to the input signal generator circuits and threshold voltage generator circuit, such as due to the switching on or off of output loads, will result in these circuits having substantially identical frequency responses and amplitude versus time responses.
    Type: Grant
    Filed: October 30, 1987
    Date of Patent: October 3, 1989
    Assignee: Gazelle Microcircuits, Inc.
    Inventors: Mark E. Fitzpatrick, Gary R. Gouldsberry, Yat-Sum Chan, Richard F. Pang
  • Patent number: 4868427
    Abstract: The present electrical circuit is capable of coupling operation between other circuits which may have different signal levels, such as small-swing ECL-like signals and large-swing TTL-like signals.
    Type: Grant
    Filed: October 30, 1987
    Date of Patent: September 19, 1989
    Assignee: Gazelle Microcircuits, Inc.
    Inventors: Mark E. Fitzpatrick, Yat-Sum Chan, Gary R. Gouldsberry