A very accurate measurement system for multielectrode capacitive sensors

Fac. of Electr. Eng., Delft Univ. of Technol.
IEEE Transactions on Instrumentation and Measurement (Impact Factor: 1.79). 05/1996; 45(2):531 - 535. DOI: 10.1109/19.492781
Source: IEEE Xplore


A very accurate capacitance-measurement system consisting of a
discrete capacitance-dependent oscillator and a microcontroller has been
developed. It can measure multielectrode capacitors with capacitances up
to 2 pF, with an accuracy of 100 ppm with respect to a reference
capacitor. The resolution amounts to 50 aF with a total measurement time
of 300 ms

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