三軸加速度計與共振磁力通結構整合分頻多工電路之設計

Abstract

本論文提出混和訊號微機電製程下，完成三軸加速度計及磁力計暨讀出電路設計，採用分頻多工之讀出電路同時讀出加速度及磁力訊號，並且利用將感測器操作在共振頻上之設計來降低三軸感測器之面積至0.3mm2。 加速度計操作範圍在±4g內，對應X、Y、Z軸加速度靈敏度為191.7aF/g、 245.3aF/g與191.1aF/g。而磁力計操作範圍在±70μT內，對應X、Y、Z軸磁場靈敏度為19.6aF/μT、19.9aF/μT與20.3aF/μT，而後利用讀取電路可將加速度計靈敏度提升至298.3mV/g、386.4mV/g與297.6mV/g；而磁力計為2.18mV/μT、2.31mV/μT與2.39mV/μT分別對應X、Y、Z軸。電路方面，加速度計的解析度為 0.27μg/√Hz、0.21μg/√Hz與0.27μg/√Hz，磁力計為9.66μT/√Hz、9.12μT/√Hz與8.81μT/√Hz分別對應X、Y、Z軸。利用專業微機電設計軟體，具體分析模擬微機電運動行為及電路特性，完成微機電與電路整合設計。

A monolithic design of three-axis accelerometer and Lorentz-force magnetometer in a sole structure with frequency division multiplexing readout circuit fabricated in standard 0.18μm 1P6M Complementary Metal-Oxide-Semiconductor technology (CMOS) has been proposed. The sensor is operating on the resonant frequency and it provides a way to realize an area efficiency sensor which area is 0.3mm2. The sensing range of sensor is ±70μT and ±4g. The capacitance sensitivity is 191.7aF/g, 245.3fF/g, and 191.1fF/g for X, Y, and Z-axis acceleration; 19.6aF/μT, 19.9aF/μT, and 20.3aF/μT for X, Y, and Z-axis for magnetic field. The sensitivity of full system is designed to be 298.3mV/g, 386.4mV/g, and 297.6mV/g for X, Y, Z-axis acceleration; 2.18mV/μT, 2.31mV/μT, and 2.39mV/μT for X, Y, and Z-axis magnetic field. The resolution of circuit is 0.27μg/√Hz, 0.21μg/√Hz, and 0.27μg/√Hz for X, Y, and Z-axis for acceleration; and 9.66μT/√Hz, 9.12μT/√Hz, and 8.81μT/√Hz for X, Y, Z-axis for magnetic field.