A 13.5b-ENOB Second-Order Noise-Shaping SAR with PVT-Robust Closed-Loop Dynamic Amplifier

📋 论文概要

本文提出一种13.5位有效位数的二阶噪声整形SAR ADC，采用PVT鲁棒的闭环动态放大器实现残差积分，兼顾了传统闭环OTA的鲁棒性和动态放大器的能效优势。该设计在低功耗下实现了高分辨率，并解决了PVT变化下性能退化的难题。

💡 主要创新点

• 提出PVT鲁棒的闭环动态放大器，结合闭环OTA的稳定性和动态放大器的低功耗特性，实现残差积分。
• 采用二阶噪声整形技术，在SAR ADC中实现高分辨率，同时保持能效优势。
• 通过闭环结构抑制PVT变化对放大器增益和带宽的影响，增强了鲁棒性。

🏷 关键词

📄 原文摘要

Linxiao Shen1, Abhishek Mukherjee1, Wei Shi1, David Z. Pan1, Nan Sun1 University of Texas, Austin, TX, 2Tsinghua University, Beijing, China 1 Noise shaping (NS) SAR ADCs combine the merits of SAR and ∆Σ ADCs, and can simultaneously achieve high power efficiency and high resolution. The key operation in an NS SAR is the residue integration. One way to implement it is to use a conventional closed-loop OTA [1-2]. It is robust against PVT variation and can realize a sharp noise transfer function (NTF), but it consumes static power and is does not scale easily. Another way is to use a passive filter [3-4]. It does not consume any static current, but its NTF is less aggressive. Moreover, because the gain of a passive filter is low, its suppression of the comparator noise is weak. An open-loop dynamic amplifier (DA) can be placed before the passive filter to reduce noise and power, but its gain varies with PVT [5-6]. To ensure stability,

👥 作者与机构

Xiyuan Tang1, Xiangxing Yang1, Wenda Zhao1, Chen-Kai Hsu1, Jiaxin Liu2,