A 14b 4.6GS/s RF DAC in 0.18µm CMOS for Cable Head-End Systems

📋 论文概要

该论文介绍了一款14位4.6GS/s的射频数模转换器，采用0.18µm CMOS工艺，面向有线电视头端系统应用。通过低压晶体管保护等电路设计技巧，在高速下实现了高精度，解决了传统DAC在射频频率下的性能瓶颈。

💡 主要创新点

• 采用低压晶体管保护技术，使高速开关管在3.3V供电下安全工作，提升转换速率。
• 通过优化偏置和驱动电路，实现了14位分辨率下4.6GS/s的超高采样率。
• 针对有线电视头端系统，优化了输出功率和线性度，满足射频发射需求。

🏷 关键词

📄 原文摘要

Paul Kalthoff3, Ajay Kuckreja4, Geir Ostrem3 Maxim Integrated, North Chelmsford, MA, 2Maxim Integrated, Woodstock, GA, Maxim Integrated, Colorado Springs, CO, 4Maxim Integrated, Boulder, CO 1 the other input is driven to about 0.25V+Vgs. As a result, the sources of M1/M2, which connect to the drain of the cascode switch in Fig. 22.7.3, are biased at 1.8V while their drains are set to 3.3V–Vgs by M7/M8. Accordingly, M1/M2 can be faster low-voltage 180nm transistors since they are protected from the 3.3V supply during normal operation. To protect them during startup, shutdown, or an inactive clock, M5/M6 are turned on by a simple detector (not shown) whenever the supplies or bias currents are not valid or the clock is inactive. 3 Cable head-end systems typically employ multiple QAM modulator signal chains to synthesize the entire TV spectrum for triple-play services, resulting in high power, cost, and size. The DAC reported here can directly synthesize 160

👥 作者与机构

Brian Brandt1, Dan McMahill2, Miaochen Wu1,