CAPACITIVE SENSOR AND ANGULAR VELOCITY SENSOR

摘要

PROBLEM TO BE SOLVED: To provide a high-sensitivity capacitive sensor with high S/N ratio, capable of detecting a minute change of a capacitance, adding a resonance frequency adjusting function by an electrostatic force, and reducing an effect of an excitation circuit.

SOLUTION: The capacitive sensor includes a physical quantity detection element wherein the capacitance changes according to a change of a physical quantity; an AC signal generating means for applying an AC signal to the physical quantity detection element; a capacity detector generating an AC voltage according to an electric charge to be charged and discharged to the physical quantity detection element by the AC signal generating means; and a ΔΣ modulator generating a ΔΣ modulation signal sequence according to an amplitude of the AC voltage to be generated by the capacity detector.

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