Patents by Inventor Malcolm Drummond

Malcolm Drummond 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: 7506014
    Abstract: A plasma control system including a direct digital synthesizer (DDS) for generating more than one individual RF power signal, where the individual RF power signals are combined to define a combined RF power signal. The DDS includes an accumulator which receives a phase increment signal that defines a frequency of a frequency signal generated by the accumulator. The frequency signal is split and input to a plurality of adders. Each adder receives a phase offset signal that defines a phase shift of the frequency signal input to that particular adder. The phase increment signal and phase offset may be stored to reduce the startup portion of the plasma control system.
    Type: Grant
    Filed: August 6, 2004
    Date of Patent: March 17, 2009
    Inventor: Malcolm Drummond
  • Publication number: 20060031273
    Abstract: A plasma control system including a direct digital synthesizer (DDS) for generating more than one individual RF power signal, where the individual RF power signals are combined to define a combined RF power signal. The DDS includes an accumulator which receives a phase increment signal that defines a frequency of a frequency signal generated by the accumulator. The frequency signal is split and input to a plurality of adders. Each adder receives a phase offset signal that defines a phase shift of the frequency signal input to that particular adder. The phase increment signal and phase offset may be stored to reduce the startup portion of the plasma control system.
    Type: Application
    Filed: August 6, 2004
    Publication date: February 9, 2006
    Inventor: Malcolm Drummond