A Distortion-Free VCO-Based Sensor-to-Digital Front-End Achieving 178.9dB FoM and 128dB SFDR with a CalibrationFree Differential Pulse-Code Modulation Technique

📋 论文概要

提出一种基于VCO的无失真传感器数字前端，解决了可穿戴传感器中运动伪影导致的大动态范围和线性度挑战，实现了178.9dB FoM和128dB SFDR，且无需校准。

💡 主要创新点

• 基于VCO的无失真前端架构，避免了传统LNA在低电压下的线性度限制。
• 采用校准自由的差分结构，简化了系统复杂度并提升了鲁棒性。
• 实现高SFDR（128dB）和高FoM（178.9dB），同时维持低功耗和小面积。

🏷 关键词

📄 原文摘要

Motion and stimulation artifacts encountered in wearable sensors present difficult dynamic range (DR) and linearity challenges: AFEs need to be able to resolve μV-level signals in the presence of artifacts up to 100s of mV in amplitude while maintaining linearity without saturation, such that the signal of interest can be readily recovered during post-processing. Since it is not possible to build an amplifier with appreciable gain and linearity for >100mV inputs under <1V SoC-compatible supply, most high-DR AFEs instead incorporate an LNA into a ∆$-based ADC-direct architecture [1-3]. However, as many emerging wearable devices desire single-chip integration in scaled CMOS for size and digital performance considerations, conventional ∆$Ms, which rely on voltage-domain building blocks, suffer from reduced intrinsic gain and headroom. Instead, time-domain quantization through VCO-based AFEs benefits from scaled CMOS

👥 作者与机构

Jiannan Huang, Patrick P. Mercier

University of California, San Diego, CA