一种新型挠性轴内置式扭摆微加速度计的设计

针对扭摆式加速度计的结构特点，为了有效利用硅片面积和提高质量块质量，设计了一种新型挠性轴内置于质量块的扭摆式加速度计，该结构具有检测电极和力反馈电极。根据结构设计参数，推导出中心敏感电容、等效质量、机械灵敏度的参数表达式。利用扭摆加速度计的数学模型，建立了加速度计表头系统级模型，并结合接口电路进行闭环整体仿真，调整校正环节参数，得到闭环系统性能指标。最后进行初步开环测试，测得加速度计的灵敏度为33mV/g，非线性度2.29%。

Design of a Novel Torsional Z-Axis Accelerometer

A novel Z-axis accelerometer with its torsion bars inside the sense element was presented, easy to form the asymmetric mass and achieve maximum usage of the die. The sensor was fabricated using ordinary bulk micromachining process. It has sensing electrodes and force-feedback electrodes. The behavior of the sensor is modeled according to its mathematic principles, enabling the co-simulation with the interface circuit in a close-loop mode. The open loop mode test shows a sensitivity of 33 mV/g and a nonlinearity of 2.29%.