Injectable microstimulator for functional electrical stimulation

  • G. E. Loeb
  • C. J. Zamin
  • J. H. Schulman
  • P. R. Troyk
North Sea: Transducers and Electrodes


A family of digitally controlled devices is constructed for functional electrical stimulation in which each module is an hermetically sealed glass capsule that is small enough to be injected through the lumen of a hypodermic needle. The overall design and component characteristics of microstimulators that receive power and command signals by inductive coupling from a single, externally worn coil are described. Each device stores power between stimulus pulses by charging an electrolytic capacitor formed by its two electrodes, made of sintered, anodised tantalum and electrochemically activated iridium, respectively. Externally, a highly efficient class E amplifier provides power and digitally encoded command signals to control the amplitude, duration and timing of pulses from up to 256 such microstimulators.


Functional electrical stimulation Microstimulators 


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Copyright information

© IFMBE 1991

Authors and Affiliations

  • G. E. Loeb
    • 1
  • C. J. Zamin
    • 1
  • J. H. Schulman
    • 2
  • P. R. Troyk
    • 3
  1. 1.Biomedical Engineering UnitQueen's UniversityKingstonCanada
  2. 2.Alfred E. Mann Foundation for Scientific ResearchSylmarUSA
  3. 3.Pritzker Institute of Medical EngineeringIllinois Institute of TechnologyChicagoUSA

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