A 90MS/s 11MHz Bandwidth 62dB SNDR Noise-Shaping SAR ADC

📋 论文概要

该论文提出了一种噪声整形的逐次逼近（SAR）模数转换器（ADC），旨在提升高分辨率下的能效。通过采用噪声整形技术，在保持高采样率（90MS/s）的同时实现了62dB的SNDR和11MHz带宽，解决了传统SAR ADC在高分辨率时因比较器噪声和DAC精度导致的能效瓶颈。

💡 主要创新点

• 首次将噪声整形技术应用于SAR ADC架构，通过环路滤波器实现量化噪声的整形，从而在不增加过多功耗的情况下提升有效分辨率。
• 采用动态比较器和简化的DAC设计，避免使用低噪声预放大器，降低了功耗和电路复杂度。

🏷 关键词

📄 原文摘要

In recent years, charge-redistribution SAR (Successive Approximation) ADCs have exhibited the highest conversion efficiencies for ADCs with moderate resolution and bandwidth [1-3]. For effective resolutions beyond 10b or so, however, the accuracy of the SAR circuit blocks limits the overall energy efficiency of the converter. At high resolutions, for instance, the DAC voltages become small compared to the input-referred noise of a dynamic comparator, necessitating an additional power-hungry, low-noise pre-amplifier to drive the comparator. To improve the resolutions of SAR ADCs, this work introduces a technique to decouple the accuracy of the comparator from the resolution of the ADC. In this paper, we introduce a low-OSR (Oversampling Ratio) noise-shaping SAR ADC that leverages noise-shaping to increase the resolution of a conventional SAR ADC. The converter uses an 8b capacitor DAC and achieves an ENOB of

👥 作者与机构

Jeffrey Fredenburg, Michael Flynn

University of Michigan, Ann Arbor, MI