Design of wireless data and power transmission for nerve cuff stimulation

• Main Authors: Chung-Kai Chen, 陳忠鍇
• Other Authors: Jia-Jin Chen
• Format: Others
• Language: en_US
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/08579710949265840371

碩士 === 國立成功大學 === 醫學工程研究所碩博士班 === 90 === 　　The functional neuromuscular stimulation system has been developed and applied to restore the lost neural function in a variety of applications. Due to the advances in microelectronics, micromachining, biomaterials, and biocompatible package technology, the microstimulator system can be fabricated in a miniaturized and implantable type. However, the domestic researches in neuromuscular stimulation are still limited in the utilization of surface stimulation. In order to provide better stimulation selectivity as well as eliminate the long wire connecting electrodes and controller, therefore, we developed a miniaturized and wireless total implantable microstimulator system. This new technology will become a new alternative for the rehabilitation of neurological disorders. 　　Before fully fabricated with VLSI, current study is to design an implanted neuromuscular stimulation system by using the discrete electronic components. This entire implantable system includes external transmission circuit and implanted microstimulator. The external unit transmits the commands and data as well as the power necessary for the internal unit via wireless telemetry. This wireless transcutaneous transmission is achieved by high efficiency class-E amplifier and inductive coupling technique. The implanted microstimulator is externally controlled and powered by a modulated radio frequency signal. The receiver circuitry of the implant provides the stably regulated voltage and demodulates the data from radio frequency signal. The microstimulator has controllable constant current stimulation channels for nerve stimulation and blocking purpose. 　　We have successful designed, implemented, and tested all the functional blocks of implantable neuromuscular stimulation system. A high efficiency class E power transmitter with self-oscillating was designed for providing RF power and data to implant, whose efficiency can be up to 90%. In the implanted device, the microstimulator is built on the double-layer of printed circuit board in 3 cm diameter by using electronics discrete components. The overall power consumption of implanted device was measured around 30 mW. Thus, this implantable microstimulator system can operate precisely when the distance between the transmitter coil and receiver coil is within 3 cm. Within this distance, lateral displacement of receiver coil is allowed as long as it is inside the area of transmitting coil. This prototype implantable microstimulator can generate two channels of wide range stimulation specifications. This prototype currently can be used for acute animal experiment and for a basis of ASIC design in the future.