一种基于40 nm CMOS工艺的40 Gbit/s低噪声跨阻放大器  

A 40 Gbit/s Low Noise Transimpedance Amplifier Based on 40 nm CMOS Process

作　　者：刘杨[1,2] 祁楠 刘力源 刘剑[1,2] 吴南健 LIU Yang;QI Nan;LIU Liyuan;LIU Jian;WU Nanjian(State Key Lab.for Superlattices and Microstructures,Institute of Semicond.,Chinese Academy of Sci.,Beijing 100083,P.R.China;College of Materials Sci.and Opto-Electronic Technol.,Univ.of Chinese Academy of Sci,Beijing 100049,P.R.China)

机构地区：[1]中国科学院,半导体研究所,半导体超晶格国家重点实验室,北京100083 [2]中国科学院大学材料科学与光电技术学院,北京100049

出　　处：《微电子学》2020年第6期771-776,共6页Microelectronics

基　　金：国家自然科学基金资助项目(61874115);北京市科技计划项目(Z191100004819006)。

摘　　要：采用40 nm CMOS工艺,设计了一个工作在40 Gbit/s数据速率的高速低噪声跨阻放大器(TIA)。为了同时兼顾噪声和带宽性能,创造性提出了一种多级串联跨阻放大器结构。输入级采用基于反相器结构的伪差分跨阻放大器,通过增加反馈电阻来减小输入电流噪声,第二级的前向运放用来抑制后级均衡器的噪声,第三级用连续时间线性均衡器(CTLE)对前级不足的带宽进行补偿,后面的三级限幅放大器(LA)对电压信号进一步放大。限幅放大器利用并联电感峰化技术和负跨导技术来提高带宽和增益。最终,信号由输出驱动器(OD)输出到片外,输出驱动器采用T-COIL技术。仿真结果表明,整条链路可以实现84 dBΩ和63 dBΩ的跨阻增益,带宽分别为31 GHz和34 GHz,输入电流积分噪声(rms)为1.75μA。Based on a 40 nm CMOS technology, a high speed low noise transimpedance amplifier(TIA) was designed to operate at a data rate of 40 Gbit/s. In order to consider both noise and bandwidth performance, a multi-stage series transimpedance amplifier structure was creatively proposed. The input stage used a pseudo-differential transimpedance amplifier based on the inverter structure. The input current noise was reduced by increasing the feedback resistance. The forward operational amplifier of the second stage was used to suppress the noise of the equalizer in the subsequent stage. The continuous time linear equalizer(CTLE) was used for the compensation of the lack of bandwidth in the previous stage. The latter three-stage limiting amplifier(LA) further amplified the voltage signal. Limiting amplifiers used shunt inductor peaking and negative transconductance techniques to increase bandwidth and gain. The final signal was output off-chip by the output driver(OD). The output driver used T-COIL technology. Simulation results showed that the entire link could achieve transimpedance gains of 84 dBΩ and 63 dBΩ, bandwidths of 31 GHz and 34 GHz, respectively. The input current integral noise(rms) was 1.75 μA.

关 键 词：光接收机模拟前端 低噪声跨阻放大器 连续时间线性均衡器 限幅放大器 

分 类 号：TN722.3[电子电信—电路与系统] TN432