This article describes a discrete-time zoom analog-to-digital converter (ADC) intended for audio applications. It uses a coarse 5-bit SAR ADC in tandem with a fine third-order delta–sigma modulator ( $\Delta \Sigma \text{M}$ ) to efficiently obtain a high dynamic range. To minimize its over-sampling ratio (OSR) and, thus, its digital power consumption, the modulator employs a 2-bit quantizer and a loop filter notch. In addition, an extra feed-forward path minimizes the leakage of the SAR ADC’s quantization noise into the audio band. The prototype ADC occupies 0.27 mm ² in a 0.16- $\mu \text{m}$ technology. It achieves 109.8-dB DR, 106.5-dB SNDR, and 107.5-dB SNR in a 20-kHz bandwidth while dissipating 440 $\mu \text{W}$ . It also achieves state-of-the-art energy efficiency, as demonstrated by a Schreier FoM of 186.4 dB and an SNDR FoM of 183.6 dB.

中文翻译：

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440μW，109.8dB DR，106.5dB SNDR离散时间缩放ADC，具有20kHz带宽

本文介绍了一种用于音频应用的离散时间缩放模数转换器（ADC）。它与一个精细的三阶delta-sigma调制器配合使用一个粗5位SAR ADC（ $ \ Delta \ Sigma \ text {M} $ ），以有效地获得较高的动态范围。为了使过采样率（OSR）和数字功耗最小，该调制器采用了2位量化器和环路滤波器陷波。此外，额外的前馈路径可将SAR ADC量化噪声泄漏到音频频带的可能性降至最低。ADC原型在0.16中 占据0.27 mm ² $ \ mu \ text {m} $ 技术。它在20kHz带宽内实现109.8dB DR，106.5dB SNDR和107.5dB SNR，同时耗散440 $ \ mu \ text {W} $ 。它还实现了最先进的能效，如186.4 dB的Schreier FoM和183.6 dB的SNDR FoM所示。