Patents by Inventor Thomas W. Wiesmann, deceased

Thomas W. Wiesmann, deceased 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).

  • Analog-to-digital converter with offset voltage polarity inversion
    Patent number: RE34428
    Abstract: There is provided according to the invention a method and apparatus for eliminating or minimizing the error due to amplifier offset or drift error in an integrating dual slope analog-to-digital converter. The converter is provided with a switching and control arrangement whereby the integrating capacitor is charged for one-half of the predetermined charging time as a function of the sum of the levels of the unknown signal and the error signal. The integrating capacitor is charged for the remaining half of the predetermined time period as a function of the difference of the levels of the unknown signal and the error signal so that the capacitor reaches a level of charge which is a function of the level of the unknown signal substantially unaffected by the level of the error signal.
    Type: Grant
    Filed: March 6, 1992
    Date of Patent: November 2, 1993
    Assignee: John Fluke Mfg. Co., Inc.
    Inventors: Richard E. George, A. Brinkley Barr, Thomas W. Wiesmann, deceased