微机械陀螺闭环驱动电路的新方法

A Novel Closed-Loop Drive Circuit for the Micromachined Gyroscope

闭环驱动方式是目前高性能微机械陀螺的主流驱动方式,大部分的闭环驱动电路采用了自动增益控制模块以稳定输出信号的幅度,但是,采用AGC模块会限制电路的线性工作范围,而且输出摆幅有限,因此制约了微机械陀螺系统的灵敏度和稳定性。基于以上不足,在建立微机械陀螺系统等效电路模型的基础上,提出一种新颖的解决方案,采用比较器代替AGC模块,实现对陀螺输出信号幅度的控制,这种方案不仅电路结构更为简单,而且增大了整体电路的线性工作范围,能够始终输出满量程的驱动信号。

The closed-loop drive circuit is widely used in high performance micromachined gyroscopes. Most of the closed-loop drive circuit consists of an AGC module to control the amplitude of the output signal. But the AGC module may restrict the linear operational range of the whole circuit and limit the amplitude of the output signal, so that deteriorates sensitivity and stability of the gyroscope system. The equivalent model of the closed-loop drive system is investigated, based on this, a novel closed-loop drive circuit is presented. In this circuit, a comparator is used to instead of the AGC circuit, which overcomes the disad- vantages of limited linear operational range and limited output signal amplitude.