Title :
Towards a closed-loop transmitter system with integrated class-D amplifier for coupling-insensitive powering of implants
Author :
Valente, Virgilio ; Eder, Clemens ; Demosthenous, Andreas ; Donaldson, Nick
Author_Institution :
Dept. of Electr. & Electron. Eng., Univ. Coll. London, London, UK
Abstract :
The efficiency of an inductive power transfer link is greatly affected by misalignment between the coils, caused by the patient´s movement, after implantation. In this paper we present the preliminary design of a coupling-insensitive system with an integrated class-D transmitter, suitable for powering epidural stimulation implants. The operation of the system is based on closed-loop modulation of the power delivered to the implant, to compensate for losses of coupling between coils after implantation. An integrated transmitter with efficiencies above 90% was designed to operate between 1 MHz and 14 MHz. The circuit design employs 0.18-um high-voltage CMOS technology. Simulations are presented to verify the operation of the circuit.
Keywords :
CMOS integrated circuits; amplifiers; biomedical electronics; closed loop systems; inductive power transmission; power supplies to apparatus; prosthetics; transmitters; circuit design; closed loop modulation; closed loop transmitter system; coil misalignment between; coupling insensitive implant powering; coupling insensitive system design; epidural stimulation implants; frequency 1 MHz to 14 MHz; high voltage CMOS technology; inductive power transfer link efficiency; integrated class-D amplifier; integrated class-D transmitter; integrated transmitter; patient movement; size 0.18 mum; Coils; Couplings; Delay; Impedance; Implants; Transmitters; Voltage measurement;
Conference_Titel :
Electronics, Circuits and Systems (ICECS), 2012 19th IEEE International Conference on
Conference_Location :
Seville
Print_ISBN :
978-1-4673-1261-5
Electronic_ISBN :
978-1-4673-1259-2
DOI :
10.1109/ICECS.2012.6463708
