Patents by Inventor Carl J. Hoffmann

Carl J. Hoffmann 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).

  • Load distribution among parallel DC-DC converters
    Patent number: 4371919
    Abstract: A control circuit (36) on the primary side of a converter senses the output voltage and is useful for modulating the drive pulse width of a switching transistor (30). An averaging circuit (78) averages the drive pulse and compares this average with an average of the drive pulses for all switching transistors in a system of parallel converters to produce an error signal. In response to the error signal, the drive pulse width is varied so that the load current is distributed evenly among the parallel converters to improve the system efficiency.
    Type: Grant
    Filed: April 29, 1981
    Date of Patent: February 1, 1983
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: Michael W. Andrews, Carl J. Hoffmann