高精度音频Sigma-Delta调制器综述

孙奥运; 温培旭; 邵淮先; 王桉楠; 鲁毅; 章飚; 曾永红; 张章

doi:10.11999/JEIT231208

高精度音频Sigma-Delta调制器综述

doi: 10.11999/JEIT231208

1.
合肥工业大学微电子学院合肥 230601
2.
天津津航计算技术研究所天津 300308

基金项目: 国家自然科学基金(U19A2053)，安徽省自然科学基金(2308085MF207)，模拟集成电路国家重点实验室开放课题(JCKY2022210C001)

详细信息

作者简介:
孙奥运：男，博士生，研究方向为高精度模数转换器设计

温培旭：男，硕士生，研究方向为高精度模数转换器设计

邵淮先：男，硕士生，研究方向为混合信号芯片设计

王桉楠：男，博士生，研究方向为混合信号芯片设计

张章：男，教授，研究方向为混合信号芯片设计

通讯作者:
张章　zhangzhang@hfut.edu.cn

中图分类号: TN45
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- 被引次数: 0
出版历程
- 收稿日期: 2023-11-01
- 修回日期: 2024-04-23
- 网络出版日期: 2024-05-11
- 刊出日期: 2024-05-30

A Review of High-Resolution Audio Sigma-Delta Modulator

1.
School of Microelectronics, Hefei University of Technology, Hefei 230601, China
2.
Tianjin JinHang Computing Technology Research Institute, Tianjin 300308, China

Funds: The National Natural Science Foundation of China (U19A2053), The Natural Science Foundation of Anhui Province (2308085MF207), The National Laboratory of Science and Technology on Analog Integrated Circuit (JCKY2022210C001)

摘要

摘要: Sigma-Delta(Σ-Δ)模数转换器(ADC)基于过采样和噪声整形技术，可实现高分辨率，具有无源器件匹配性要求低、结构简单等特点。在高精度音频领域，Σ-Δ ADC能够实现高动态范围和良好的功率效率得到了广泛的关注和应用。近年来，依托先进工艺、先进技术进行低功耗高精度的音频ADC的设计已经成为新的研究热点。然而随着工艺技术向低节点的持续发展、电源电压的不断降低，使得Σ-Δ ADC的电路设计更具挑战性。该文对高精度音频Sigma-Delta调制器的离散型设计、连续型设计的研究现状进行综述，为高精度音频Sigma-Delta调制器设计提供理论支撑，并给出研究前景展望。
- Sigma-Delta(Σ-Δ)调制器 /
- 高精度 /
- 音频
Abstract: Sigma-Delta (Σ-Δ) Analog-to-Digital Converter (ADC) is based on oversampling and noise shaping techniques to achieve high-resolution, and is characterized by low passive component matching requirements and simple structure. In high-resolution audio applications, Σ-Δ ADC has gained widespread attention and applications since it can achieve high dynamic range with good power efficiency. Recently, there has been a growing research trend in designing low-power, high-resolution audio ADCs using advanced processes and technologies. However, with process technology going to lower nodes and the reduction of supply voltages, the circuit design becomes more challenging. This paper reviews the state-of-the-art of the discrete-time and continuous-time design of high-resolution audio Sigma-Delta modulators, provides theoretical background for the design of high-resolution audio Sigma-Delta modulators, and gives research prospects.
- Sigma-Delta (Σ-Δ) Modulator /
- High-Resolution /
- Audio

HTML全文

图 1 离散型调制器示意图

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图 2 开关电容积分器

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图 3 积分器中的放大器拓扑架构

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图 4 基于动态运放和基于反相器的积分器示意图

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图 5 闪速量化器和SAR量化器示意图

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图 6 使用DEM算法的反馈DAC架构

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图 7 VCO作为相位积分器的经典模型

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图 8 基于计数器的VCO量化器

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图 9 FIR DAC技术的反馈DAC架构

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表 1 Sigma-Delta ADC中DAC不匹配误差的数字校准总结

	伪数据加权平均^[56]	数据加权平均^[58]	比较数据加权平均^[59]
特点	适合于低比特量化，音调行为相对于DWA有所下降	结构简单，具备1阶噪声整形能力， OSR较低时有较大的谐波，有固定音调存在	具有2阶噪声整形，能够有效抑制谐波，没有明显音调行为

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