A Wireless Power and Bi-Directional Data Transfer System Using A Single Inductive Link for Biomedical Implants

This paper presents a wireless power and data conversion unit, designed to receive power and data via a single inductive link with a focus on applications in implanted biomedical devices. The system provides a reliable power supply for electronic circuits and supports bi-directional half-duplex data communication through frequency and load shift keying (FSK and LSK) modulation schemes. The wireless power and data transfer (WPDT) system utilizes a full-wave active rectifier operating at a frequency of 13.56 MHz, a bandgap voltage reference, and a 1.8 V low-dropout (LDO) voltage regulator to optimize the power supply for the electronic circuitry. The proposed data conversion unit is capable of demodulating data at a data rate of up to 1.35 Mbps. The proposed system is fabricated using a 180-nm 1.8/3.3 V CMOS process and occupies a total area of 0.305 mm2 at the implant site. The system was evaluated with a coupled coil inductive link in testing.