SBAT014 October   2023 AFE4432 , AFE4460 , AFE4500 , AFE4950


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Applications like optical heart rate and SpO2 monitoring are based on the principle of Photoplethysmography (PPG). The primary challenges in PPG signal acquisition on a wrist-worn variable are: (i) small sensor size, (ii) relatively weak signal on wrist (low perfusion index), and (iii) interferers like ambient light and motion artifacts. TI’s signal chain for PPG signal acquisition has 3 unique characteristics that help achieve excellent signal quality even in the most challenging conditions: (i) high gain transimpedance amplifier (TIA) to improve the SNR, (ii) DC offset cancellation DAC at the input, and (iii) noise reduction filter to reduce the optical noise bandwidth. These unique features help achieve excellent dynamic range at extremely low power consumption.

GUID-20231025-SS0I-5T93-NGFP-BBJTV38FHWQJ-low.svgHeart Rate Monitoring
GUID-20231025-SS0I-FKBT-V6NS-CBKCGGWCN6PC-low.svgSpO2 Monitoring
GUID-20231025-SS0I-HQNJ-PNB8-KVRW92HRHG6L-low.svgBlock Diagram

Recommended Parts

AFE4432Ultra-small, ultra-low-power, high-SNR, integrated analog front ends (AFE) for wearable optical biosensing with FIFO
AFE4460High-SNR, ultra-low-power, integrated AFE for wearable optical biosensing with FIFO
AFE4950Ultra-small integrated AFE for wearable optical heart-rate monitoring and SpO2
AFE4500Integrated analog front end (AFE) for bioimpedance analysis and electrical and optical biosensing

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