大摆幅输出的高速线性行波驱动器

A high-speed linear large-swing push-pull drivers

基于0.13μm SiGe BiCMOS工艺设计了高速线性行波马赫-曾德尔调制器(Mach-Zehnder Modulators,MZM)驱动器。驱动器主要由三个部分组成,分别是输入级、输出级和直流消除(Direct Current Offset Compensation,DCOC)。输入级在差分对的发射极引入可变电容和可变电阻来实现增益可调的功能,在输出节点采用了并联电感峰化技术来提高带宽;输出级中采用了击穿电压倍增技术来获得大摆幅输出电压,以及采用了并联电感峰化技术来提高带宽;DCOC通过在行波MZM驱动器的输出和输入之间建立反馈以消除直流失调,并且采用了一阶低通滤波器以保证环路稳定。仿真结果显示,驱动器的增益可以在较大的范围内可调,DCOC环路的相位裕度高达82°,最高工作速率为100 Gb/s,输出Vpp约为4 V,可以很好地驱动行波MZM。

A high-speed linear push-pull Mach-Zehnder Modulators(MZM)driver based on 0.13μm SiGe BiCMOS process is proposed in this paper.The driver circuit is composed of 3 components,including the input stage,the output stage and direct current offset compensation(DCOC).A variable gain is achieved by placing variable resistances and variable capacitances in the emitter of the input stage,and the bandwidth is expanded by shunt inductive peaking technology.The output stage utilizes the breakdown voltage multiplier to attain a large-swing,and shunt inductive peaking technology is implemented to get a wide bandwidth.The DCOC builds a feedback between the output and the input of the driver,and utilizes a low pass filter to ensure loop stability.The simulation results demonstrate that the driver gain can be adjusted in a wide scale,and the phase margin,the operating rate and the voltage output swing are 82°,100 Gb/s,4 V,respectively,which can drive the push-pull MZM well.