title: Closed-loop class E transcutaneous power and data link for microimplants.
abstract: Magnetic transcutaneous coupling is frequently used for power and data transfer to implanted electronic devices. The proposed development of MicroImplants, small enough to be injected through a hypodermic needle suggest the need for a high-efficiency magnetic transcutaneous link. This paper describes the use of a multifrequency transmitter coil driver based upon the Class E topology. The development of a "high-Q approximation" which simplifies the design procedure is presented. A closed-loop controller to compensate for transmitter and receiver variations, and a method of data modulation, using synchronous frequency shifting are described. The closed-loop Class E circuit shows great promise, especially for circuits with unusually low coefficients of coupling. Currents of several amperes, at radio frequencies, can easily and efficiently be obtained.
authors.affiliation: Pritzker Institute of Medical Engineering, Illinois Institute of Technology, Chicago 60616.
authors.forename: P R
authors.initials: PR
authors.lastname: Troyk
authors.forename: M A
authors.initials: MA
authors.lastname: Schwan
mesh_terms: D004867:Equipment Design; D019736:Prostheses and Implants; D013686:Telemetry / Q000295:instrumentation*; D004561:Transcutaneous Electric Nerve Stimulation / Q000295:instrumentation*