一款基于AGC-PI结构的微陀螺闭环驱动电路芯片  

An AGC-PI Based Closed-Loop Drive Circuit on Chip for Micro-Gyroscope

作　　者：吴焕铭[1,2] 杨海钢[1] 尹韬[1] 程小燕[1,2] 

机构地区：[1]中国科学院电子学研究所,北京100190 [2]中国科学院研究生院,北京100049

出　　处：《纳米技术与精密工程》2014年第1期56-62,共7页Nanotechnology and Precision Engineering

基　　金：国家自然科学基金资助项目(61106025);中国科学院;国家外国专家局创新团队国际合作伙伴计划;国家高技术研究发展计划(863计划)资助项目(2012AA012301)

摘　　要：比例积分(PI)控制器是微陀螺自动增益控制(AGC)闭环驱动电路中的重要模块,常被用来改善闭环驱动电路的瞬态响应特性.但是,传统的PI控制器电路存在功耗、面积大的缺点.针对此问题,提出了一种Gm-C结构的PI控制器,其仅由一个片内的跨导放大器和片外电容电阻网络即同时实现了减法、比例和积分功能,显著减小了芯片功耗和面积.此外,提出了一种带温度补偿的跨阻放大器(TIA)结构的读出电路,将驱动轴振动速度幅值的温漂系数从补偿前的1 640×10-6/℃提高到了114×10-6/℃.设计的驱动电路芯片在0.35μm标准CMOS工艺下实现,工作电压为5 V.其中PI控制器的静态功耗小于1 mW,面积仅为0.18 mm×0.08 mm.芯片与微陀螺的联合测试结果表明,在PI控制器的比例系数和积分系数分别设置为10和200时,闭环驱动电路有最佳的瞬态响应.Proportionalintegral （PI） controller is an important module in automatic gain control （AGC） based gyroscope drive circuit and commonly used to improve the transient response of the closedloop drive circuit. However, the drawbacks of large power and large chip area consumption exist in conven tional PI controllers. This paper proposes a GmC based PI controller, which consists of only one opera tional transconductance amplifier （OTA） onchip and a resistorcapacitor （RC） network offchip, thus realizing the PI control and subtract function simultaneously. As a result, its chip area and power con sumption are reduced significantly. Furthermore, a readout circuit of transimpedanee amplifier （TIA） structure with temperature compensation is proposed, so that the temperature drift coefficient of the vibra ting velocity amplitude in drive axis is improved from 1 640 x 106/℃ to 114 x 106/℃. The drive cir cuit on chip is implemented through a 0.35 μm CMOS technology with 5 V supply voltage. The static power consumption of PI controller is less than 1 mW and its area is only 0.18 mm x 0.08 ram. Experi ments on a gyroscope show that the closedloop drive circuit achieves the best transient response when the proportional coefficient and integral coefficient are set as 10 and 200, respectively.

关 键 词：微陀螺 闭环驱动电路 PI控制器 温度补偿 

分 类 号：TN432[电子电信—微电子学与固体电子学]