Low-Power Photoplethysmogram Acquisition Integrated Circuit with Robust Light Interference Compensation

Sensors

Jongpal Kim²  Jihoon Kim¹  Hyoungho Ko¹ 

[1] Chungnam National University, Daejeon 34134, Korea;Samsung Electronics Inc., Suwon 16678, Korea;

关键词: photoplethysmogram;    transimpedance amplifier;    ambient light cancellation;    automatic offset compensation;    automatic emitted light compensation;   

DOI  :  10.3390/s16010046

来源: mdpi

【 摘 要 】

To overcome light interference, including a large DC offset and ambient light variation, a robust photoplethysmogram (PPG) readout chip is fabricated using a 0.13-μm complementary metal–oxide–semiconductor (CMOS) process. Against the large DC offset, a saturation detection and current feedback circuit is proposed to compensate for an offset current of up to 30 μA. For robustness against optical path variation, an automatic emitted light compensation method is adopted. To prevent ambient light interference, an alternating sampling and charge redistribution technique is also proposed. In the proposed technique, no additional power is consumed, and only three differential switches and one capacitor are required. The PPG readout channel consumes 26.4 μW and has an input referred current noise of 260 pArms.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.