A fully integrated physical activity sensing circuit for implantable pacemakers

ABSTRACT

This 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 2.1uVrms input noise. Detailed circuit specifications, measurements, and a comparative analysis of the system performance are presented.

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INDEX TERMS

Primary Classification:
  B. Hardware
  B.7 INTEGRATED CIRCUITS
      B.7.1 Types and Design Styles
          Subjects: Input/output circuits

General Terms:
Design, Measurement

Keywords:
CMOS, analog design, biomedical, low-power