Patents by Inventor Doug R. Farrenkopf

Doug R. Farrenkopf 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: 5397934
    Abstract: An apparatus and method for adjusting the effective threshold voltage of a MOS transistor is disclosed. Reference voltage generation circuitry is used for generating a first voltage signal. Threshold voltage monitoring circuitry that includes the MOS transistor is used for measuring the effective threshold voltage of the MOS transistor and for generating a second voltage signal. Feedback circuitry compares the first voltage signal to the second voltage signal and adjusts the effective threshold voltage of the MOS transistor so that the first voltage signal is substantially equal to the second voltage signal. The effective threshold voltage of the MOS transistor is adjusted by adjusting its source-body voltage potential.
    Type: Grant
    Filed: April 5, 1993
    Date of Patent: March 14, 1995
    Assignee: National Semiconductor Corporation
    Inventors: Richard B. Merrill, Doug R. Farrenkopf
  • Patent number: 5296409
    Abstract: A method of making N-channel and P-channel junction field-effect transistors using a modified CMOS process that simultaneously makes complementary metal-oxide-semiconductor transistors, or a modified BiCMOS process that simultaneously makes bipolar transistors and complementary metal-oxide-semiconductor transistors. Making junction field effect transistors using the basic CMOS process requires mask changes and an additional mask, etch, and implant step. Making junction field effect transistors using the BiCMOS process only requires mask changes.
    Type: Grant
    Filed: May 8, 1992
    Date of Patent: March 22, 1994
    Assignee: National Semiconductor Corporation
    Inventors: Richard B. Merrill, Doug R. Farrenkopf