Power Receiving Circuit Design of Single-ended Biological Capacitive WPT for Artificial Retina System

This paper describes the power receiving circuit design of biological capacitive wireless power transfer (C-WPT) for an artificial retina system. To make system design simpler, we propose a single-ended C-WPT. By designing in this way, the system can be designed based on the GND of the RF source, so the RF source and the rectifier circuit can be designed single-ended. First, we make clear the principle of the single-ended capacitive coupler and describe its design method. Our C-WPT does not require the balun, thus the coupler can be connected to a single-ended rectifier circuit. The element values required for the rectifier circuit connected by an equivalent circuit were calculated and the rectifier circuit was designed. Finally, the coupler and rectifier circuit were fabricated, and experimental measurements using porcine skin with a thickness of about 5 mm yielded that the power received was 75.3 mW at 434 MHz.