Study Of Key Technologies Of Implantable Electrical Nerve Stimulator Powered By RF

Electrical nerve stimulation plays an important role in the treatment of neurological disorders and nerve injury rehabilitation. With the development of microelectronic technology, communications technology and bio-materials technology, electrical nerve stimulation has changed from the traditional percutaneous stimulation to the modern implantable stimulation. The latter has outstanding advantages for the stimulation positioning accuracy, therapeutic effect, and small stimulation current, light discomfort pain. On targets distinction, implantable electrical nerve stimulation includes deep brain stimulation, spinal cord stimulation, vagus nerve stimulation, sacral nerve stimulation, phrenic nerve stimulation, and other treatment modalities; distinction by treatment of disease, it has enormous clinical significance on Parkinson's disease, chronic pain, Epilepsy, bladder dysfunction, respiratory dysfunction, hypertension, obesity, and other diseases.The basic structure and function of different types of implantable electrical nerve stimulation is similar. Mainly, it includes the main stimulator implanted, as well as the external controller in vitro applications. And it involves a number of key technologies, such as low power consumption, high reliability, biological compatibility, seal and electrodes. In this paper, the subject is funded by Chongqing Municipality research project (Project No. : 7768) and carries out two-way short-range radio communication based on Zigbee protocol between the implanted stimulator and the external controller, RF transcutaneous energy transfer, as well as generation of bi-phase constant-current stimulation pulse of the stimulator implanted, and other key technology research. Firstly, using time to wake up and synchronization strategies of Zigbee communication protocol to achieve a regular two-way wireless data transmission, and helps to realize closed-loop control of state information feedback and stimulation parameters reprogrammed. Secondly, using MSP430 microprocessor to control output of bi-phase constant-current stimulation pulse, and helps to realize high precision, small power, and the output of stimulation waveform will not vary with the fluctuation of load impedance. Lastly, adopting PCB antenna and PCB magnetic coupling inductor coil design to realize the system's PCB integration.Nowadays, the relevant technology and products of implantable electrical nerve stimulation remains in the hands of a few large companies abroad, such as Medtronic, Cyberonics, St. Jude and Boston Scientific. And it is very expensive, which is a serious impediment of the popularization and application in the developing countries. On the basis of the analysis of the current technology and market demand both at home and abroad, this study will provide some reference for the domestic independent research and development of implantable electrical nerve stimulator.