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PubMed · 10230140

Preamplifier with a second-order high-pass filtering characteristic.

Y D Lin·C D Tsai·H H Huang·D C Chiou·C P Wu
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Abstract

A new preamplifier for suppressing low-frequency interference is presented. The proposed preamplifier, with its front end being implemented by an instrumentation amplifier, enjoys the following advantages: differential high-pass filtering, high input impedance, high common--mode rejection ratio and low passive sensitivity. This circuit can be realized with commercial operational amplifiers with enough phase margin, or fabricated in a chip for practical measurement of physiological signals.

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Y D Lin, C D Tsai, H H Huang, D C Chiou, C P Wu. 1999. Preamplifier with a second-order high-pass filtering characteristic.. https://doi.org/10.1109/10.759062

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