Closed-Loop Transductor-Compensated Class E Driver for Inductive Links

When a class E circuit is employed to drive an inductive link, very little tolerance is allowed on the inductance value of the transmitter coil. Deformable coils are thus not compatible with an open- loop class E design. By connecting a transductor in series with the transmitter inductance, it is possible to keep the total class E inductance constant, regardless of the transmitter coil deformation. This is achieved through a control loop that steers the transductor to the appropriate inductance value. For the realized closed-loop circuit, class E regime is maintained for inductance variations of the transmitter coil of up to 27 %. The principal advantage of transductor control compared to earlier reported techniques, is the fixed frequency of operation.

[1]  M. Kazimierczuk,et al.  Resonant Power Converters , 1995 .

[2]  Glenn A. DeMichele,et al.  Inductively-coupled power and data link for neural prostheses using a class-E oscillator and FSK modulation , 2003, Proceedings of the 25th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (IEEE Cat. No.03CH37439).

[3]  Robert Puers,et al.  An autonomous bladder pressure monitoring system , 2002 .

[4]  No Sokal,et al.  CLASS-E - NEW CLASS OF HIGH-EFFICIENCY TUNED SINGLE-ENDED SWITCHING POWER AMPLIFIERS , 1975 .

[5]  D. Graetzer,et al.  Transductor-regulators for switched-mode power supplies , 1980 .

[6]  R. Puers,et al.  Self Tuning Inductive Powering For Implantable Telemetric Monitoring Systems , 1995, Proceedings of the International Solid-State Sensors and Actuators Conference - TRANSDUCERS '95.

[7]  Robert Puers,et al.  Self-tuning inductive powering for implantable telemetric monitoring systems , 1996 .

[8]  W. Ko,et al.  Design of radio-frequency powered coils for implant instruments , 1977, Medical and Biological Engineering and Computing.

[9]  C.M. Zierhofer,et al.  High-efficiency coupling-insensitive transcutaneous power and data transmission via an inductive link , 1990, IEEE Transactions on Biomedical Engineering.

[10]  Frederick H. Raab,et al.  Idealized operation of the class E tuned power amplifier , 1977 .

[11]  P.R. Troyk,et al.  Closed-loop class E transcutaneous power and data link for MicroImplants , 1992, IEEE Transactions on Biomedical Engineering.

[12]  Babak Ziaie,et al.  A self-oscillating detuning-insensitive class-E transmitter for implantable microsystems , 2001, IEEE Transactions on Biomedical Engineering.