Autonomous dual-mode (PAM2/4) serial link transceiver with adaptive equalization and data recovery
Autonomous dual-mode (PAM2/4) serial link transceiver with adaptive equalization and data recovery
复制标题
具有自适应均衡和数据恢复功能的自主双模 (PAM2/4) 串行链路收发器
DOI：
10.1109/jssc.2004.842863
复制
发表时间：
2005
影响因子：
5.4
通讯作者：
M. Horowitz
中科院分区：
文献类型：
--
作者：
V. Stojanović;A. Ho;B. Garlepp;Fred Chen;Jason Wei;G. Tsang;E. Alon;R. Kollipara;C. Werner;J. Zerbe;M. Horowitz
本文介绍了一种自适应均衡，双模（PAM 2单抽头DFE/PAM 4）0.13 /spl μ/m CMOS收发器芯片，以及用于不断适应链路的技术。有趣的是，只需进行微小的修改，就可以使用实现PAM 4系统所需的相同硬件来实现PAM 2环路展开单抽头判决反馈均衡（DFE）接收器。使用基于数据的更新滤波的自适应均衡允许连续更新，同时最小化所需的采样器前端硬件，并显著降低了多级信令方案中的实现成本。为了使发射器能够适应信道，链路使用共模信令在现有的一对导线上创建反向信道通信路径。该设计采用三电平归零信令方案，允许接收器同时提取电压和定时基准，并最大限度地减少所需的接收器硬件。测量结果表明，该反向信道实现了可靠的通信，而不会对前向链路产生明显的影响，反向信道数据速率高达16 Mb/s，摆幅为20-100 mV。
This paper describes an adaptively equalized, dual-mode (PAM2 one-tap DFE/PAM4) 0.13 /spl mu/m CMOS transceiver chip, and the techniques used to continuously adapt the link. Interestingly, with only minor modification the same hardware needed to implement a PAM4 system can be used to implement a PAM2 loop-unrolled single-tap decision-feedback equalization (DFE) receiver. Adaptive equalization using data-based update filtering allows continuous updates while minimizing the required sampler front-end hardware and significantly reduces the cost of implementation in multi-level signaling schemes. To allow the transmitter to adapt to the channel, the link uses common-mode signaling to create a back-channel communication path over the existing pair of wires. The design uses a three-level return-to-null signaling scheme which allows the receiver to simultaneously extract voltage and timing references and minimize the required receiver hardware. The measured results indicate that this back-channel achieves reliable communication without noticeable impact on the forward link for back-channel data rates of up to 16 Mb/s and swings of 20-100 mV.