A fully integrated physical activity sensing circuit for implantable pacemakers

PostprintThis paper shows the implementation of a fully integrated Gm-C 0.5-7Hz bandpass filter-amplifier with gain G=400, for a piezoelectric accelerometer which is part of a rate adaptive pacemaker. The fabricated circuit operates up to 2V power supply, consumes only 230nA current, and achives 2.1μVrms input noise. Detailed circuit specifications, measurements, and a comparative analysis of the system performance are presented