A 977μW Capacitive Touch Sensor with Noise-Immune Excitation Source and Direct Lock-In ADC Achieving 25.2pJ/step Energy Efficiency

📋 论文概要

该论文提出一种977μW电容触摸传感器，采用噪声免疫的激励源和直接锁定ADC，有效抑制显示噪声、荧光灯噪声和充电器噪声，实现了25.2pJ/step的高能效。

💡 主要创新点

• 提出噪声免疫的激励源设计，通过消除多种外部噪声干扰提升信噪比。
• 采用直接锁定ADC架构，在低功耗下实现高精度电容检测。

🏷 关键词

📄 原文摘要

China 1 2 Capacitive touch systems play a crucial role in user interfaces across many applications, such as mobile devices, desktop PCs, and interactive whiteboards [1-6]. In capacitive touch systems, various sources of noise present significant challenges for achieving a high signal-to-noise-ratio (SNR) while keeping good energy efficiency, including display noise, fluorescent lamp noise, and charger noise (Fig. 26.5.1, top). Although fully differential sensing can cancel out display noise, channel mismatch still results in leakage into the signal chain. Moreover, fluorescent lamp noise and charger noise affect the touch-related channels and cannot be eliminated by fully differential sensing circuits. However, the noise sources exhibit a distinct spectral characteristic, with the energy

👥 作者与机构

Xiangdong Feng1, Zhiyu Wang1, Yekan Chen1, Tianyi Cai1, Yangfan Xuan1,

Changgui Yang1, Weixiao Wang1, Yunshan Zhang2, Zhong Tang3, Yuxuan Luo1, Bo Zhao1 Zhejiang University, Hangzhou, China Microaiot, Hangzhou, China 3 Vango Technologies, Hangzhou,