Abstract：The accuracy of micro-capacitance detection systems in gyroscopes directly determines the rotor displacement measurement accuracy, which in turn determines the overall accuracy of the gyroscope. A micro-capacitance detector was developed in this study based on ring-diode demodulation for the special structure of a spinning-rotor gyro. The system output gain variations were studied to develop a gain algorithm based on the leakage minimization principle with a noise reduction algorithm to reduce the output noise. This micro-capacitance detection method based on ring diodes reduces the noise which improves the capacitance detection resolution. Tests show that the optimized circuit gives a capacitance resolution of better than 20.0 aF and a resolution at the unit bandwidth of better than 0.258 aF·Hz-1/2 which is excellent capacitance measurement accuracy.
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2021, Vol. 61 
