Abstract
Early detection and treatment of cardiovascular diseases (CVDs) can be significantly enhanced through the use of flexible wearable electrocardiogram (ECG) sensors, potentially reducing CVD-related mortality. This paper introduces an ECG-on-Chip (EoC) solution tailored for flexible ECG sensors, incorporating novel features to address common challenges in wearable ECG technology. The EoC integrates a chopper-stabilized capacitively-coupled instrumentation amplifier (CS-CCIA), ensuring a high common-mode rejection ratio (CMRR) and low noise performance. Performance is further boosted via a positive feedback loop (PFL) and a programmable gain amplifier (PGA) with shared on-chip calibration logic, which enhances input impedance and minimizes gain variability to ensure consistent algorithm performance. Additionally, a secondary chopping technique is employed to further reduce noise, achieving an input-referred noise level of 454 nVrms. The embedded algorithm within the EoC is designed to extract clinically meaningful features, facilitating robust real-time arrhythmia analysis. Fabricated using a 0.18 µm CMOS process, the EoC consumes 14.9 µW with a supply voltage of 1.2 V. The algorithm’s efficacy has been validated over 0.4 million heartbeats, demonstrating a sensitivity of over 99.7% for R-peak detection and 98.3% for arrhythmia analysis. To demonstrate practical application, the EoC has been integrated with a commercial Bluetooth low energy (BLE) transceiver, forming a wireless arrhythmia monitoring sensor equipped with dry electrodes. This system consumes 292.04 µW in arrhythmia-aware transmission mode, supporting 13 days of operation with a 30 mAh thin-film battery.
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Acknowledgements
This work was supported in part by National Natural Science Foundation of China (Grant Nos. 62350710216, 62104145) and National Key Research and Development Program of China (Grant No. 2019YFB2204500).
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Xu, X., Suo, Y., Zhao, Y. et al. A dry-electrode enabled ECG-on-Chip with arrhythmia-aware data transmission. Sci. China Inf. Sci. 68, 122405 (2025). https://doi.org/10.1007/s11432-024-4196-0
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DOI: https://doi.org/10.1007/s11432-024-4196-0


