Fully-Analog Motion Artifact Elimination Circuit for Compact and Low-Power Ambulatory Ecg Decvices

This work presents a fully-analog ECG motion artifact elimination circuit that can extract and remove undesired signal components from the ECG waveform corrupted with motion artifacts without using digital processing. The key concept of the proposed scheme is extracting the undesired signal component from the ECG waveform corrupted with motion artifacts by performing moving average, downsampling, and linear interpolation operations. In this case, the huge [Formula: see text], [Formula: see text]-peaks that can mislead the extraction process are detected and excluded from the undesired component. Furthermore, the proposed algorithm can be effectively implemented with discrete-time analog blocks, including the high-[Formula: see text] switched-capacitor biquad. As a result, the proposed circuit can be easily incorporated in the ECG sensor frontend, which can lead to a compact and low-power ambulatory ECG monitoring device. The proposed fully-analog ECG motion artifact elimination circuit is realized using CMOS 0.18[Formula: see text][Formula: see text]m technology with a core area of [Formula: see text][Formula: see text]mm and power consumption of 6.5[Formula: see text][Formula: see text]W. The prototype ECG device, including the proposed circuit, was verified with 22 test participants within the age group from 10 to 65. Test results show the average Percent Root Mean Square Difference (PRD) for the ECG waveforms obtained under various motions (walking, working, and sleeping) compared to steady-state ECG is 21.64% and 5.61% before and after motion artifact elimination.