Two-Way Communication Digital Power Controllers for Wireless Retinal Prosthesis Systems

Abstract

Power-efficient digital controllers are proposed for wireless retinal prosthetic systems. Power management plays an important role in reducing the power consumption and avoiding malfunctions in implantable medical devices. In the case of implantable devices with only one-way communication, the received power level is uncertain because there is no feedback on the power status. Accordingly, system breakdown due to inefficient power management should be avoided to prevent harm to patients. In this study, digital power controllers were developed for achieving two-way communication. Three controllers—a forward and back telemetry control unit, a power control unit, and a preamble control unit—operated simultaneously to control the class-E amplifier input power, provided command data to stimulators, monitored the power levels of the implanted devices, and generated back telemetry data. For performance verification, we implemented a digital power control system using a field-programmable gate array and then demonstrated it by employing a wireless telemetry system.

Integrated High-Temporal-Resolution and High-Density Subretinal Prosthesis Using a Correlated Double-Sampling Technique

“…As a result, the retina chip achieved a maximum stimulus period of 20 Hz, and a current deviation under 1.2 μA on the standard deviation of the overall stimulus current. For future work, the proposed high-density stimulation chip will be merged with a wireless power transmission system [ 20 ] and packaged for clinical trials.…”

Sensors, Circuits, and Systems for Biomedical Applications

“…In recent years, numerous studies have demonstrated the beneficial effects of administering appropriate electrical stimulation to humans, such as for treating diseases, reducing pain, and replacing the function of existing nerves [ 1 , 2 , 3 , 4 ]. To provide a glimpse into the ongoing research on electrical stimulation, we introduce several examples of spinal cord stimulation and retina prosthesis research.…”

“…Zawawi R.B.A. et al proposed the addition of back telemetry to a retina prosthesis system which wirelessly transmits power, allowing the external transmitter to confirm whether the transmitted power is being received successfully by the system [ 2 ]. Moreover, in the event of abnormal reception, the receiver is designed to stop functioning until successful reception is achieved.…”