本研究以磁力計結合加速度計的設計理念，設計可控制2軸同步作動或單軸作動增強之磁力計，此磁力計使用UMC 0.18 m CMOS製程，結構尺寸為995×932 μm^2，同時將電路製作於晶片內，完成單晶片(SoC)。該元件可以量測直流與交流磁場。 量測直流磁場時需給予交流的驅動電流，可分為同動模式與增強模式。同動模式可量測一平面的向量，適合應用於位置檢測的回授系統，使用驅動交流電流60 mA時，Y軸磁場的靈敏度為18.5 V/T，Z軸磁場的靈敏度為2.9 V/T。增強模式只需調整驅動電流頻率和相位，即可使Y軸磁場的靈敏度增加為37.5 V/T，大約2倍，能清楚量測到地磁，進行方位檢測的應用。 量測交流磁場時需給予直流的驅動電流1 mA，即可量測BLDC馬達的轉速及轉向，可用於馬達控制。 ;This design allows control of 2-axis simultaneous operation or single-axis enhanced operation of the magnetometer. This magnetometer uses UMC 0.18 μm CMOS process. The circuitry is integrated within the chip, resulting in a single-chip system-on-chip (SoC) solution. The MEMS structure has dimensions of 995 × 932 μm² and is capable of measuring both DC and AC magnetic fields. When measuring DC magnetic fields, an AC driving current is required. In simultaneous mode, the device can measure the magnetic field vector of a single plane, making it suitable for use in position detection feedback systems. With a driving AC current of 60 mA, the sensitivity for the Y-axis magnetic field is 18.5 V/T, and for the Z-axis magnetic field, it is 2.9 V/T. In superimposed mode, simply adjusting the frequency and phase of the driving current can increase the Y-axis magnetic field sensitivity to 37.5 V/T, approximately doubling it. This enhancement allows for clear measurement of the geomagnetic field, enabling applications in orientation detection. When measuring AC magnetic fields, a DC driving current of 1 mA is required. This allows for the measurement of the rotational speed and direction of a BLDC motor, which can be used for motor control.
