Patents by Inventor Douglas J. Dromgoole

Douglas J. Dromgoole 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).

  • Current estimating circuit for switch mode power supply
    Patent number: 5457620
    Abstract: In a switch mode power supply the switch current of the power switch is connected to a low pass filter network during the time interval when current is flowing through the power switch. The filter network is disconnected from the power switch when switch current is not flowing. This technique takes advantage of the fact that the average current through the power switch during its conduction interval is either equal to the output current of the power supply, or is proportional with the ratio between the average switch current and the output current being the fixed isolation transformer turns ratio.
    Type: Grant
    Filed: July 30, 1993
    Date of Patent: October 10, 1995
    Assignee: AT&T IPM Corp.
    Inventor: Douglas J. Dromgoole