A Circuit System Design for Implantable Multi-channel neural stimulator

Abstract

More than 161 million people worldwide are suffering from ablepsia [1], and among them, ten million are blind result from the photoreceptor loss due to degenerative retinal diseases. For these patients, neural stimulating proved to be an effective method of rehabilitation. This method is based on conceive of substituting an artificial device for the defective photoreceptor in patients functionally [2]. Multi-channel neural stimulator is a part of the device. In the design of multi-channel neural stimulator, the kernel problems are concerning the output stimulating current. Micro, bipolar, and steady output current is required to protect guarantee safety and effectiveness of this stimulator [3]. Furthermore, a simple and tiny structure is essential for the stimulator to implanting into human bodies. This paper focused on the design of a circuit serves as the DA converter and stimulation generator, which is made up of a Micro Controller Unit (MCU), a Digital to Analog Convector (DAC) and Amplifiers. The results of simulation made by Multisim shows that this circuit can put out bi-phasic micro and steady current whose precision of the current is 5µA. The size of all the intraocular part of the whole device is 36mm×28mm.