面向光通信应用的CMOS 28 Gbps低功耗高抖动容限CDR电路设计

为了解决光模块中高功耗芯片恶化激光调制器性能，以及解决收发端时钟基准偏差导致误码率高的问题，设计了一款低功耗高抖动容限的时钟数据恢复电路（CDR）。通过采用压控振荡器（VCO）型全速时钟的CDR系统架构和电感峰化的时钟缓冲技术，降低了CDR芯片的功耗；通过在CDR积分通路中引入零点补偿电阻，提高了CDR的抖动容限。该CDR采用CMOS 65 nm工艺设计和1.1 V电源供电，后端仿真结果表明：当CDR电路工作在28 Gbps时，功耗是2.18 pJ/bit，能容忍的固定频差是5 000 ppm，恢复时钟的抖动峰峰值是5.6 ps，抖动容限达到了设计指标，且满足CIE-25/28G协议规范。

A CMOS 28 Gbps Low Power and High Jitter Tolerance CDR Circuit in Optical Communication Applications

Aimed at the problems that the performance of laser modulator with high power chips in optical modules becomes deteriorated, and bit error rate caused by the clock reference deviation between transceivers is high, a low power and high jitter tolerance clock and data recovery circuit (CDR) is proposed in this paper. By adopting a technology of voltage controlled oscillator (VCO) type and full speed CDR system architecture, and using a technology of an inductance peaking in clock buffer, the power consumption of the CDR chip is reduced. By introducing a zero point compensation resistor in the CDR integration path, the jitter tolerance of the CDR is improved. The CDR is designed with CMOS 65 nm process and supplied with 1.1 V. The back end simulation results show that when the CDR circuit works at 28 Gbps, the power consumption is 2.18 pJ/bit. When the frequency difference of the transceiver is 5 000 ppm, the jitter peak to peak value of the recovered clock is 5.6 ps, and the jitter tolerance meets the needs of design index and the CIE25/28G protocol specification.