Mohan Neethu, Awwad Falah, Albastaki Nabil, Atef Mohamed
Electrical and Communication Engineering Department, United Arab Emirates University, Al Ain 15551, United Arab Emirates.
Sensors (Basel). 2024 Jun 24;24(13):4097. doi: 10.3390/s24134097.
This study presents an integrated analog front-end (AFE) tailored for photoplethysmography (PPG) sensing. The AFE module introduces a novel transimpedance amplifier (TIA) that incorporates capacitive feedback techniques alongside common drain feedback (CDF) TIA. The unique TIA topology achieves both high gain and high sensitivity while maintaining low power consumption. The resultant PPG sensor module demonstrates impressive specifications, including an input noise current of 4.81 pA/sqrt Hz, a transimpedance gain of 18.43 MΩ, and a power consumption of 68 µW. Furthermore, the sensory system integrates an LED driver featuring automatic light control (ALC), which dynamically adjusts the LED power based on the strength of the received signal. Employing 0.35 µm CMOS technology, the AFE implementation occupies a compact footprint of 1.98 mm × 2.475 mm.
本研究提出了一种专为光电容积脉搏波描记法（PPG）传感量身定制的集成模拟前端（AFE）。AFE模块引入了一种新型跨阻放大器（TIA），该放大器结合了电容反馈技术以及共漏反馈（CDF）TIA。独特的TIA拓扑结构在保持低功耗的同时实现了高增益和高灵敏度。所得的PPG传感器模块展示出令人印象深刻的规格，包括4.81 pA/√Hz的输入噪声电流、18.43 MΩ的跨阻增益以及68 µW的功耗。此外，该传感系统集成了一个具有自动光控制（ALC）功能的LED驱动器，它根据接收信号的强度动态调整LED功率。采用0.35 µm CMOS技术，AFE实现占用的紧凑面积为1.98 mm × 2.475 mm。
