Patents by Inventor Tho Huyhn

Tho Huyhn 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).

  • Battery impedance measurement apparatus
    Patent number: 5137020
    Abstract: A battery impedance measurement apparatus for battery powered implantable medical apparatus in which current source means and reference impedance means are selectively connected across the battery after it has been isolated from the medical apparatus, and the resulting currents of interest are digitized to provide a factor directly related to the value of the internal impedance of the battery. The digitized value may be telemetered out of the implanted medical apparatus to enable critical decisions to be made based on the remaining life of the implanted battery. The same measurement apparatus can be used to form an accurate end-of-life signal.
    Type: Grant
    Filed: November 29, 1990
    Date of Patent: August 11, 1992
    Assignee: Medtronic, Inc.
    Inventors: David A. Wayne, Tho Huyhn, Jeff Ireland