A Dual-Mode FSK Wireless Power and Data Transfer System With 1.1 Mbps Data Rate and Rectifier Output Power of 148 mW for Implantable Medical Applications

This paper proposes a wireless power and data transfer (WPDT) system for implantable medical applications, featuring a simple structure, high data rate (DR), and efficient power transmission. To streamline the frequency-shift keying (FSK) data transmission link, the FSK modulator integrates merely one oscillator and one frequency divider, while the FSK demodulator requires only one D flip-flop and one delay unit. This minimalist design generates two FSK carrier signals with a large frequency difference, simultaneously enhancing the data transmission rate and reducing the bit error rate (BER). To meet the WPDT system's requirements for high power transmission under transient conditions and low coupling coefficients, a coupled network capacitive compensation technique is employed. This method significantly enhances the power transmission capability of one carrier frequency, enabling greater power delivery to the load (PDL) of that carrier frequency during non-data transmission periods. Relevant circuits were fabricated using the 180 nm BCD process, and a prototype WPDT system based on these circuits has been successfully developed. Test results show that under a low coupling scenario (17.5 mm coil spacing), the system achieves a PDL of 148 mW while maintaining a DR of 1.1 Mbps with a BER below 10${}^{-8}$. This work fully verifies the system's feasibility and provides an efficient, reliable technical solution for wireless power supply and data transmission in implantable medical devices.