Pseudo-Resistor-Based ECG Amplifier: Design, Implementation and Temperature Characterization

Biomedical signal amplifiers are fundamental in various medical applications for acquiring crucial biological signals such as ECG, EEG, and EMG. The use of pseudo-resistors has been recently studied for biological amplifiers, mainly because of their fast recovery time after interference pulses, which are frequent in such applications. The previous studies on pseudo-resistors are limited to simulation, modeling, and implementing some narrow-bandwidth amplifiers. For the first time, this study uses the piecewise linear (PWL) model integrated with pseudo-resistors to design a tailored circuit for ECG applications, with 0.04 Hz to 2 kHz bandwidth for the full application temperature range. The circuit is fully modeled, simulated, and characterized, fine-tuning the feedback capacitance values to optimize performance within the crucial temperature range for biomedical applications. This full bandwidth amplifier represents a significant advancement in biomedical signal amplification technology, ensuring comprehensive signal fidelity allied to fast recovery response.