微电容加速度计系统的设计

为了在总体上把握硅微加速度计的设计,建立了叉指式硅微加速度计的机械模型,研究了全差分二阶∑-ΔADC接口检测电路提取加速度信号,优化了开关电容电路来检测微小电容变化量,运用微机电专用设计软件CoventorWare对系统的机电混合模型进行仿真,并给出数字和模拟的分析结果,为加速度计系统的机械部分和电路部分的设计提供整体的更接近实际的设计参考。

Design of micromachined capacitive accelerometer system

In order to hold the design of the accelerometers,the model of silicon micromachined capacitive accelerometer in mechanical domain is designed,a fully-differential 2nd order sigma-delta analog-to-digital converter(ADC) for use as an interface circuit for accelerometers to sense the acceleration is researched,and the circuit to sense the little change of the capacitor is improved.The MEMS design tools ConentorWare are used to deal with the simulation about the system combined the mechanical and electronical models,and show the results.Useful reference in design of whole system,which is closer to the practice is provided.