Integration Design of Wide-Dynamic-Range MEMS Magnetometer and Oscillator

This paper presents a Lorentz current-based MEMS magnetometer integrated with MEMS oscillator. The auto capacitance offset calibration magnetometer can achieve a tunable sensitivity from 12 to 2.94×106 T/V and eliminate the capacitance mismatch caused by process variation under 0.084fF by SAR calibrator. The natural frequency of proposed differential oscillator is around 18.8 kHz, Q-factor of 183 under the bias voltage 20 V and at 760Torr ambient pressure. The proposed biasing method of oscillator obtains a frequency tuning range of 58510 ppm, resulting in a wide-dynamic-range which is about 107.8dB. FOM of the oscillator design is 4.75×1020 Hz2Ω2. The integrated magnetometer and oscillator is implemented in 1P6M ASIC compatible CMOS MEMS process.