A Hybrid Multipath CMOS Magnetic Sensor with 210μTrms Resolution and 3MHz Bandwidth for Contactless Current Sensing

📋 论文概要

本文提出一种混合多路径CMOS磁传感器，结合霍尔传感器和拾取线圈的优势，解决了传统CMOS霍尔传感器在高带宽下分辨率下降的问题。该传感器实现了210μTrms的分辨率和3MHz的带宽，适用于非接触电流检测应用。

💡 主要创新点

• 提出混合多路径架构，同时利用霍尔传感器在低频和中频的线性度以及拾取线圈在高频的微分特性，实现全带宽内的高分辨率。
• 在标准CMOS工艺中实现，无需额外工艺步骤，便于集成和低成本生产。

🏷 关键词

📄 原文摘要

CMOS Hall sensors are widely used as magnetic sensors due to their linearity and ease of integration [1-3]. Being essentially n-well resistors, their resolution is determined by thermal noise and so decreases with bandwidth (Fig. 11.3.1), limiting their use in wide-band current-sensing applications, such as in switchedmode power supplies, electric motor control and short-circuit detection. In contrast, the differentiating characteristic of pick-up coils means that their resolution actually improves with bandwidth (Fig. 11.3.1). This paper describes a hybrid sensor in standard CMOS that achieves wide bandwidth and good resolution by employing a Hall sensor in a low-frequency (LF) path and a coil in a high-frequency (HF) path. The sensors’ outputs are amplified by two transconductance amplifiers (gm,coil and gm,HS) and then combined by a transimpedance amplifier (TIA) (Fig. 11.3.1). The sensor achieves a resolution of

👥 作者与机构

Junfeng Jiang, Kofi Makinwa

Delft University of Technology, Delft, The Netherlands