A 10Gb/s combined equalizer in 0.18μm CMOS technology for backplane communication

This paper presents a 10Gb/s high-speed equalizer as the front-end of a receiver for backplane communication.The equalizer combines an analog equalizer and a two-tap decision-feedback equalizer in a half-rate structure to reduce the inter-symbol-interference(ISI) of the communication channel.By employing inductive peaking technique for the high-frequency boost circuit,the bandwidth and the boost of the analog equalizer are improved.The decision-feedback equalizer optimizes the size of the CML-based circuit such as D flip-flops(DFF) and multiplex(MUX),shortening the feedback path delay and speeding up the operation considerably.Designed in the 0.18μm CMOS technology,the equalizer delivers 10Gb/s data over 18-in FR4 trace with 28-dB loss while drawing27-mW from a 1.8-V supply.The overall chip area including pads is 0.6×0.7mm~2.     

10Gbit/s 0.18μm CMOS1:4分接集成电路

研究了万兆以太网接收芯片结构,并在此基础上设计、流片和测试了高速1∶4分接芯片,采用0.18 μm CMOS工艺设计的1∶4分接电路,实现了满足10GBASE-R的10.312 5 Gbit/s数据的1∶4串/并转换,芯片面积1 100 μm×800 μm,在输入单端摆幅为800 Mv,输出负载50 Ω条件下,输出2.578 Gbit/s数据信号电压峰峰值为228 Mv,抖动为 4 ps RMS, 眼图的占空比为55.9%,上升沿时间为58 ps.在电源为 1.8 V时, 功耗为 500 Mw.电路最高可实现13.5 Gbit/s的4路分接.     

低功耗0.18μm 10Gbit/s CMOS 1∶4分接器设计

为了实现光纤通信系统中高速分接器低功耗的需求,采用0.18μm CMOS工艺实现了一个全CMOS逻辑10 Gbit/s 1∶4分接器.整个系统采用半速率树型结构,由1∶2分接单元、2分频器单元以及缓冲构成,其中锁存器单元均采用动态CMOS逻辑电路,缓冲由传输门和反相器实现.在高速电路设计中采用CMOS逻辑电路,不但可以减小功耗和芯片面积,其输出的轨到轨电平还能够提供大的噪声裕度,并在系统集成时实现与后续电路的无缝对接.测试结果表明,在1.8 V工作电压下,芯片在输入数据速率为10 Gbit/s时工作性能良好,芯片面积为0.475 mm×0.475 mm,核心功耗仅为25 mW.     

1.5 V 0.35μm CMOS 3.2 Gb/s 1:4分接器设计

采用CSM 0.35μm CMOS工艺,设计了低电压高速1∶4分接器.分接器采用半时钟树型结构,由1个高速1∶2分接器和2个低速1∶2分接器级联而成.整个电路实现的基本单元为共栅动态负载锁存器.电路最高可工作在3.2 Gb/s,电源电压为1.5 V,整体电路功耗约为120 mW,芯片面积为0.675 mm×0.675 mm.