Title :
A very accurate measurement system for multielectrode capacitive sensors
Author :
Toth, Ferry N. ; Meijer, Gerard C M ; Kerkvliet, Harry M.M.
Author_Institution :
Fac. of Electr. Eng., Delft Univ. of Technol., Netherlands
fDate :
4/1/1996 12:00:00 AM
Abstract :
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
Keywords :
capacitance measurement; comparators (circuits); electric sensing devices; integrating circuits; intelligent sensors; measurement errors; microcontrollers; multiplexing; position measurement; relaxation oscillators; switched capacitor networks; 2 pF; 300 ms; SC relaxation oscillator; comparator; discrete capacitance-dependent oscillator; double-sided multiplexing; integrator; microcontroller; modified Martin oscillator; multielectrode capacitive sensors; nonidealities; nonlinearity; oscillator noise; parasitic capacitances; position sensors; quantization noise; reference capacitor; resolution; smart sensor; three-signal approach; very accurate capacitance-measurement system; Cables; Capacitance measurement; Capacitive sensors; Capacitors; Circuits; Joining processes; Microcontrollers; Multiplexing; Oscillators; Parasitic capacitance;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
