摘要摘要 MEMS ( Micro Electro Mechanical systems , 即微电子机械系统)是建立在微米/ 纳米技术基础上的前沿技术,其利用微电子技术和微加工技术制造各种性能优异的微型化传感器。加速度传感器是一种十分重要的力学传感器,随着现代科学技术(主要是 MEMS 技术)的发展,加速度传感器出现了微型化、集成化的发展趋势。信号处理电路是加速度传感器设计需要考虑的一个重要方面,集成化要求信号处理电路和加速度传感器单片集成。飞行器的加速度可以利用 MEMS 电容来表征,但该电容仅在 pF量级,对应加速度变化的电容变化量就更小了。本文针对一个差分电容式闭环加速度传感器设计了它的信号处理电路,主要包括信号的检测、滤波与放大。通过对传统电路的改进消除了寄生电容和失调电压的影响,重点分析了噪声的影响并设计了一个低噪声放大器,同时应用开关电容技术,更好地抑制噪声和易于系统集成。最终微电容信号处理电路能检测到 fF量级的电容变化。关键词:加速度传感器 MEMS 差分电容 MOS 开关微小信号检测低噪声放大器 ABSTRACT ABSTRACT MEMS ( Micro Electro Mechanical systems ) isa technology of forward position based on Micro/Nano technology. It uses microelectronic technology and micromachining to manufacture all kinds of excellent micromation sensor. Acceleration sensor isa key mechanical quantity sensor. As the development of the modern science and technology especially the MEMS technology, there is the tendency of accelerometer is micromation and integration. Signal processing circuit isa important facet of design accelerometer. Integration need integrate signal processing circuit and accelerometer sensor ina chip. The acceleration of aerocraft can use MEMS capacitance to depict, but this capacitance is only onpF level. The variation of capacitance corresponding acceleration is more littler. This paper design the signal processing circuit for a differential capacitive closed loop acceleration sensor, it including detect of the sign
