DUAL-FUNCTIONAL RESONANT MAGNETIC FIELD SENSOR

摘要

Disclosed is a dual-functional resonant based magnetic field sensor that functions as magnetic field sensor and accelerometer, respectively, comprising a sensor structure including a mass block and motion sensor electrodes, capacitance to voltage converter and amplifier to convert sensing signals of the sensor electrodes into voltage, as output signals of the magnetic field sensor, a driving circuit to provide the output signals to the mass block in the form of current, to drive the mass block to vibrate, and a selection circuit to select measurement of magnetic field or acceleration. The driving circuit may be a comparator. The selection circuit may be replaced by a filter to select frequency bands of the output signals of the converter, for simultaneously providing signals representing magnetic field and acceleration, respectively.

主权项

1. A dual-functional resonant magnetic field sensor, comprising:
a detector structure, comprising a mass block suspended in the detector structure; and two sets of displacement detection electrodes disposed on the detector structure, at both sides of the mass block along a first direction X in a plane where the mass block is arranged; a converter circuit, connected to the displacement detection electrodes of the detector structure, to convert detection results of the displacement detection electrodes into a voltage signal, as output signal of the dual-functional magnetic field sensor; a vibration driving circuit, connected to output of the converter circuit, to provide output of the converter circuit to the mass block in the detector structure in a form of current, for driving the mass block to vibrate; and a selection circuit to selectively block the driving current of the vibration driving circuit from being provided to the mass block; wherein currents provided by the vibration driving circuit flow through the mass block in a second direction Y, which is perpendicular to the first direction X in the plane where the mass block is arranged.