A 250kHz-BW 93dB-SNDR 4th-Order Noise-Shaping SAR Using Capacitor Stacking and Dynamic Buffering

📋 论文概要

该论文提出了一种采用电容堆叠和动态缓冲技术的四阶噪声整形逐次逼近寄存器（SAR）模数转换器（ADC），实现了250kHz带宽和93dB SNDR，有效解决了传统噪声整形SAR中放大器功耗高、噪声大的问题。

💡 主要创新点

• 提出电容堆叠技术，在不增加额外电容面积的情况下实现高阶噪声整形，降低了功耗和噪声。
• 采用动态缓冲技术替代传统高增益放大器，进一步减少功耗并提高能效。

🏷 关键词

📄 原文摘要

Xidian University, Xi’an, China 3 University of Texas, Austin, TX 1 2 The noise-shaping (NS) SAR is an emerging hybrid architecture that aims to combine the benefits of both SAR and ∆Σ ADCs [1-8]. The key in an NS SAR is the NS filter. As shown in Fig. 27.1.1, prior NS filter techniques can be classified into two types. The first way is to use a closed-loop amplifier-based integrator [1-3]. With sufficient gain of the amplifier, this type of integrator can realize a sharp noise transfer function (NTF). However, the high-gain multi-stage amplifier produces large noise, is power-consuming and unfriendly to technology scaling [2,3]. The second way is to use passive charge sharing to perform error feedback [4-6] or integration [7,8]. The fully passive filter avoids using closed-loop amplifiers, but it has signal attenuation issue and the resulting NTF is mild [4]. Also, due to the lack of effective gain, it suffers from large comparator noise.

👥 作者与机构

Jiaxin Liu1, Dengquan Li2, Yi Zhong1, Xiyuan Tang3, Nan Sun1,3

Tsinghua University, Beijing, China