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以ＭＥＭＳ（微型机电系统）为基础的惯性仪表在汽车、计算机、导航等领域都将有广泛的应用。为了制作出低价格、小尺寸、中等精度的微型加速度计，有必要将接口电路和敏感元件集成在一个芯片上。本文介绍了一个体加工工艺的微机械敏感元件（包括一个差动电容结构）；分析了一种ＣＭＯＳ前置缓冲放大器和增量求和（Δ）原理的静电力反馈系统并且用计算机进行了仿真；同时对系统噪音进行了讨论。这个前置缓冲放大器可以达到２２ＭＨｚ的单位增益带宽和很小的运放输入电容。Δ反馈回路可以得到高精度和高线性度的数字输出。
Inertial meters based on MEMS (Micro Electro Mechanical Systems) are widely used in the fields of automobile, computer, navigation and so on. In order to produce a low-cost, small-sized, medium precision micro accelerometer, it is necessary to integrate the interface circuit and the sensing element on a single chip. In this paper, a micromachined sensitive element (including a differential capacitor structure) is introduced. An electrostatic force feedback system based on CMOS pre-buffer amplifier and incremental summation (Δ) principle is analyzed and analyzed by computer Simulation; At the same time the system noise was discussed. This pre-buffer amplifier can achieve 22MHz unity gain bandwidth and a small op amp input capacitance. Δ feedback loop can get high precision and high linearity digital output.