Abstract
For capacitive biopotential measurement, a novel high input impedance front-end is proposed. The input impedance of the front-end can achieve more than 100 GΩ by matching the peripheral parameters. The front-end’s noise model is provided, and noise optimization is given further. The analysis shows the proposed front-end can achieve at least two orders of input impedance more than the non-inverting amplifier circuit with the same peripheral parameters at the cost of only increasing twice input-referred noise. The final experimental results verify the analysis and show the front-end’s feasibility of capacitive sensing electrocardiogram signal.
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A novel high input impedance front-end is proposed, which impedance can achieve more than 100 GΩ by matching the peripheral parameters. The analysis and noise optimization results show the proposed front-end can achieve at least two orders of input impedance more than the non-inverting amplifier circuit with the same peripheral parameters at the cost of only increasing twice input-referred noise. The final experimental results verify the analysis and show its feasibility of capacitive sensing electrocardiogram signal.
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Funding
This work was supported by the National Key R&D Program of China (No. 2016YFA0202102), the Key Technologies R&D Program of Jiangsu Province (No. BE2014712 and BE2010190), and the National Nature Science Foundation Program of China (No. 61571376 and 11304152).
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Wu, R., Tang, Y., Li, Z. et al. A novel high input impedance front-end for capacitive biopotential measurement. Med Biol Eng Comput 56, 1343–1355 (2018). https://doi.org/10.1007/s11517-017-1781-0
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DOI: https://doi.org/10.1007/s11517-017-1781-0