A 128Gb/s PAM-4 Transmitter with Programmable-Width Pulse Generator and Pattern-Dependent Pre-Emphasis in 28nm CMOS

📋 论文概要

该论文提出了一种128Gb/s PAM-4发射机，采用可编程宽度脉冲发生器和模式相关预加重技术，以降低高速PAM-4信号中的数据相关抖动和符号间干扰，从而提高眼图质量。

💡 主要创新点

• 提出可编程宽度脉冲发生器，通过调整脉冲宽度优化发射脉冲形状，减少数据相关抖动。
• 提出模式相关预加重技术，根据PAM-4数据模式动态调整预加重强度，有效补偿非相邻电平跳变带来的大幅度ISI。

🏷 关键词

📄 原文摘要

The ever-growing demands for high-bandwidth communications continuously push wireline links to operate at higher speeds. Recently reported transmitters (TXs) have achieved a data rate of more than 100Gb/s [1-6]. PAM-4 modulation, which doubles the data rate at the same symbol rate, has been widely adopted to make use of the link bandwidth more efficiently. However, the complex transitions introduce greater datadependent jitter, decreasing the horizontal eye-opening. In addition, the transitions between non-adjacent levels bring about twice or three times inter-symbol interference (ISI) compared with transitions between adjacent levels, resulting in reduced vertical eye-opening. Although a feed-forward equalizer (FFE) can be used to mitigate these issues, it is usually implemented in a de-emphasis manner in PAM-4 TXs, which reduces the output swing and lowers the signal-to-noise ratio. The proposed TX incorporates a

👥 作者与机构

Kai Sheng, Weixin Gai, Zeze Feng, Haowei Niu, Bingyi Ye, Hang Zhou

Peking University, Beijing, China