A Sub-400-nT/root Hz, 775-mu W, Multi-Loop MEMS Magnetometer With Integrated Readout Electronics

作者：Minotti Paolo^*; Brenna Stefano; Laghi Giacomo; Bonfanti Andrea G; Langfelder Giacomo; Lacaita Andrea L

来源：Journal of Microelectromechanical Systems, 2015, 24(6): 1938-1950.

DOI：10.1109/JMEMS.2015.2452316

• Microelectromechanical systems (MEMS) sensors
• magnetometers
• capacitive sensing interface
• navigation

This paper presents a novel z-axis Lorentz force magnetometer coupled with a low-power readout integrated circuit. The sensor is fabricated using an industrial process, and exploits an Al-on-polysilicon multi-loop architecture that gives a five-fold sensitivity and resolution improvement, useful for off-resonance operation. The integrated readout is based on a differential charge amplifier front-end, and designed to be balanced with the sensor in terms of noise and power consumption. The overall system, including demodulation and filtering stages, shows a programmable full-scale up to +/- 2.4 mT, limited by the electronics saturation. The bandwidth can be programmed up to 150 Hz for off-resonance operation where a sub-400-nT/root Hz resolution at 775-mu W power consumption is obtained, including the integrated readout and the Lorentz current. Perspectives on low-consumption driving oscillators for off-resonance mode are finally given. [2015-0139]

• 出版日期2015-12