Patents by Inventor Charles J. Walker

Charles J. Walker 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: 5949121
    Abstract: A temperature-indicating field effect transistor (100) includes a transistor die (101) including a drain (103), a source (105), and a gate (107). A temperature measurement device (109, 111) is thermally coupled to the transistor die (101) and electrically coupled to the gate (107). A transistor package (113) encapsulates the transistor die (101) and the temperature measurement device (109, 111). The transistor package (113) has three externally accessible terminals including a first terminal (115) connected to the drain (103), a second terminal (117) connected to the source (105), and an input terminal (119) coupled to the temperature measurement device (109, 111).
    Type: Grant
    Filed: August 2, 1996
    Date of Patent: September 7, 1999
    Assignee: Motorola Inc.
    Inventors: John R. Qualich, Charles J. Walker
  • Patent number: 4918564
    Abstract: A load driver circuit has an output transistor driving the load, with a protective circuit that, when enabled, turns off the output transistor to protect it from high current levels. A delay circuit, which responds to abnormal load conditions after the output transistor has been on for a brief interval, enables the protective circuit to cause turn-off of the output transistor.
    Type: Grant
    Filed: May 30, 1989
    Date of Patent: April 17, 1990
    Assignee: Motorola, Inc.
    Inventors: Charles J. Walker, Steve Dominguez