04806846 is referenced by 131 patents and cites 3 patents.

A relatively simple circuit for implementing a low-cost, low power, highly accurate capacitance-to-voltage converter by which to measure the unknown capacitance of a capacitor. The circuit is characterized by the ability to eliminate error due to stray capacitance sources. The circuit is implemented by a crystal controlled clock generator which produces multi-phase clock signals to control the operation of a pair of series connected field effect transistors and a buffer amplifier. The field effect transistors are alternately switched on and off to periodically charge and discharge the capacitor under measurement between a source of reference potential and the inverting input terminal of a precision operational amplifier. The output voltage of the operational amplifier tracks the capacitance of the capacitor under measurement, such that an accurate indication of its capacitance is obtained by merely reading the output of the operational amplifier.

Title
High accuracy direct reading capacitance-to-voltage converter
Application Number
7/70342
Publication Number
4806846
Application Date
July 6, 1987
Publication Date
February 21, 1989
Inventor
George L Kerber
4611 Lisann St., San Diego, 92117
CA, US
Agent
Morland C Fischer
IPC
G01R 27/26
G01R 11/52
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