Patents by Inventor John C. Fidler

John C. Fidler 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: 5198771
    Abstract: A potentiostat for an amperometric sensor uses a voltage-controlled current source (VCCS), which may be either unidirectional or, preferably, bidirectional. An error amplifier compares the potential of the sensor's reference or counter electrode, relative to ground potential, to a set-point potential. The error voltage serves as an input to the VCCS. The output of the VCCS--a current proportional to the error voltage--is supplied to the sensor's auxiliary electrode. In a steady state, the error voltage is just large enough to supply current that is equal to the current through the sensor's working and auxiliary (or counter) electrodes. The error voltage can either serve directly as an output voltage or it can be amplified without introducing a feed-back loop disturbance. The VCCS permits direct grounding of the sensor's working electrode and operation of the error amplifier at a low or moderate gain, so as to increase the circuit's frequency response and reduce the probability of oscillation.
    Type: Grant
    Filed: September 3, 1991
    Date of Patent: March 30, 1993
    Assignee: Transducer Research, Inc.
    Inventors: John C. Fidler, James P. Bobis, William R. Penrose, Joseph R. Stetter