第21卷
第7期
2013年7月
1004-924X(2013)07-1734-07
文章编号
光学精密工程
Optics and Precision Engineerinf
Vol. 21No, 7
Jul.2013
微机械陀螺检测接口建模及前置放大器优化
赵阳，裘安萍，，施芹，赵健
（南京理工大学MEMS惯性技术研究中心，江苏南京210094）
摘要：为了进一步提高微机械陀螺的极限分辨率，建立了基于SOI工艺的微机械陀螺的检测接口模型，并设计了与之相匹配的前置接口放大器。首先，根据陀螺表头的实际结构建立了微机械陀螺：表头的RC集总参数模型和微机裁陀螺检测接口的噪声模型，分析了检测接口主导噪声源及提高极限分辨率的措施。然后，在跨阻式前置放大器的基础上设计了改进的与检测接口匹配的T型前置放大器。实验结果表明：相比于跨阻式前置放大器，采用改进的T型前置放大器的等效噪声输人电流由1.18pA//Hz降低至0.27pA//Hz，对应的电容极限分辨率可达到0.62aF//Hz，结果显示，
采用与检测接口匹配的T型前置放大器提高了微机械陀螺的极限分辨率。关键词：微机械陀螺；接口模型极限分辨率；T型前置放大器
中图分类号：TH824；V666.123
文献标识码：A
doi,10, 3788/OPE. 20132107.1734
Modeling of sensing interface for micromachined
gyroscopeanditsfront-endoptimization ZHAOYang,QIUAn-ping',SHIQin,ZHAOJian
(MEMS Inertial Technology Research Center, Nanjing University of
Science and Technology,Nanjing 210094,China)
+Correspondingauthor,E-mailapqiumail.njust.edu.cn
Abstract: To improve the resolving limit of a micromachined gyrcscope, a sensing interface model for the micromachined gyroscope fabricated by Silicon on Insulator(SOl) process was established, and a matching front-end was designed, Firstly, a RC lumped paramete: model for the gyroscope was estab-lished based on the practical gyroscope structure, then a noise model for the sensing interface was built. The dominant noise source and methods to improve the resolving limit were analyzed. Finally, on the foundation of a TIA front-end, an improved T-network front-end was designed to match the sensing interface, Experimental results indicate that the T-network front-end improves the sensing in-terface equivalent input noise current from 1. 18 pA//Hz to 0. 27 pA//Hz, corresponding to a ca-pacitive resolution of o.62 aF//Hz as compared to those of the transimpedance front-end. It suggests that the improved T-network front-end can reach a better resolut:on.
Key words: micromachined gyroscope; interface model; resolving limit; T-network front-end
收稿日期：2013-02-25；修订日期：2013-03-15
基金项目：武器装备预研基金资助项目（No.9140A09011011BQ02)；国家863高技术研究发展计划资助项目