A 100MHz-BW 68dB-SNDR Tuning-Free Hybrid-Loop DSM with an Interleaved Bandpass Noise-Shaping SAR Quantizer

📋 论文概要

本论文提出一种带宽100MHz、SNDR 68dB的无调谐混合环路线性调制器（DSM），采用交错带通噪声整形SAR量化器。解决了传统连续时间DSM因RC时间常数漂移需要数字调谐、对DAC ISI和抖动敏感等问题，实现了宽带高动态范围且无需调谐。

💡 主要创新点

• 提出混合环路DSM架构，结合连续时间和离散时间优点，避免RC时间常数漂移，无需数字调谐。
• 采用交错带通噪声整形SAR量化器，实现宽带（100MHz）高SNDR（68dB）的同时降低对DAC非理想性的敏感度。

🏷 关键词

📄 原文摘要

Emerging communication and radar applications place enormous demands on ADC performance by requiring wide BW (100MHz) and high DR (70dB). Continuous-time delta-sigma modulators (CT-DSM) [1-2] are a mainstream solution as they deliver high amplifier efficiency, are easy to drive, and provide innate anti-aliasing. However, CTDSMs have some inherent drawbacks: 1) the loop filter is typically based on RC time-constants which are poorly defined and require digital tuning; 2) they do not scale with sampling frequency; and 3) they are very sensitive to DAC ISI and jitter [2]. Discretetime (DT) DSMs, such as the emerging noise-shaping (NS) SAR architecture, avoid these problems, but cannot provide the essential benefits of CT-DSMs. We propose the new hybrid-loop (HL) DSM architecture, which combines the advantages of both CT and DT DSMs and eliminates the drawbacks. Moreover, a bandpass, time-interleaved noiseshaping (TINS) SAR quantizer [3] further boosts the new architecture’s performance.

👥 作者与机构

Lu Jie, Hsiang-Wen Chen, Boyi Zheng, Michael P. Flynn

University of Michigan, Ann Arbor, MI