音叉电容式微机械陀螺接口电路设计研究

【作者】 蒋庆华；

【导师】 苑伟政；

【作者基本信息】 西北工业大学 ， 机械制造及其自动化， 2004， 硕士

【摘要】 微机械陀螺和传统陀螺相比具有体积小、重量轻、成本低、可靠性高等优点，在众多领域具有广阔的应用前景。微机械陀螺采用集成电路工艺和微细加工技术制造，尺寸微小，驱动和检测困难，目前接口电路的研究是微机械陀螺研究的重点和难点。本文针对音叉电容式微机械陀螺的接口电路设计、稳幅谐振、微弱信号检测和处理等问题开展研究。 1．设计了音叉电容式微机械陀螺开环和闭环两种驱动电路。开环电路采用方波加直流偏置的等效交流电压驱动陀螺振动，通过模拟分析了方波驱动形式对陀螺振动的影响；结合开环驱动电路，提出了闭环驱动电路方案。闭环驱动电路基于锁相原理，采用专业锁相环芯片，进一步提高了陀螺驱动模态的谐振性。 2．对小电容检测电路进行了研究。介绍了MEMS领域最常见的缓冲器电容检测方案和电荷放大器电容检测方案。重点分析了电荷放大器电容检测方案的误差源，并且给出了误差避免的措施和运算放大器的选择原则。 3．设计了音叉电容式微机械陀螺检测电路。电容检测电路采用电荷放大器方案，并且对其进行了改进；对电容检测电路的输出信号进行了分析，设计了信号检测电路，有效的分离出了输入角速度。 经过对电路性能的分析、陀螺主要参数的估算，确定所设计的电一几}北邢业人学学位论义路可以达至fJ基本要求。更多还原

【Abstract】 Micromechanical gyroscopes with advantages in small size, light weight, low cost, high reliability have great prospects in various area compared with classical gyroscopes. Micromechanical gyroscopes manufactured in IC technology combined with micromachined process has small size ,driving and detecting are difficult. Nowadays the research of the electronic interface circuit is the key point in the field of Micromechanical gyroscopes. This paper aims to finish the electronic interface circuit of the tuning fork micromechanical gyroscope detected by capacitance to ensure the vibrating of the gyroscope and to detect and process the signals.1. The driving circuit of the tuning fork micromechanical gyroscope is designed. Two schemes are introduced, the open-looped driving circuit and the closed-looped one. The open-looped driving circuit is based on the idealization of the vibration. The square wave voltage and the direct current voltage are combined to drive the gyroscope. Influences of square wave voltage are analyzed though simulation .As for the real situation of the vibration, The closed-looped driving circuit is given. Based on the principle of phase-locked, the closed-looped driving circuit is designed using the special chip.2. The circuits of small capacitive sensors are introduced in detail.The "buffer" circuit and the "’charge sense" circuit are analyzed; Sources of error in the later are introduced in detail, at the same time the solving method and the principles are given.3. The sensing circuit tuning fork micromechanical gyroscope is designed. As for the detecting circuit of the capacitances, the "charge sense" circuit are improved, and the detecting bridge is designed. Trough the analysis of the output of the detecting circuit of the capacitances, the processing circuit is designed, and the angular rate is separated :Parameters computed of the gyroscope and the performance analyzed of the circuit show that the circuit can reach the base requirement.更多还原