DiTTO: A distance adaptive over 100 mW wireless power transfer system with 1.695 Mbps uplink telemetry and a shared inductor two-output regulating rectification

Abstract

This article presents a wireless power transfer (WPT) system that incorporates a seamless uplink data telemetry and a simultaneous shared inductor dual-output (SIDO) regulating rectification (RR) under distance variation over a single WPT link. In the pursuit, a power management integrated circuit (PMIC) for a biometric smartcard that rectifies and regulates DC output in a single stage under distance and load variation using a frequency splitting phenomenon with a low power zero current detector and the sigma-delta control loop is proposed. After, the development of single-stage rectifying and regulator, a PMIC that can furthermore transfer uplink data along with SIDO-RR for electroceutical application is proposed. The proposed double charging keying (DCK) uplink data modulation method assisted by a dynamic zoom control breaks the trade-off between power delivery to loads (PDL) and uplink data such that the high data-rate uplink data telemetry no longer limits the amount of power delivered to the loads. Furthermore, DCK alleviates the design difficulty in simultaneous uplink data telemetry and RR. This work achieves a 1.695 Mbps uplink data rate while delivering up to 108 mW to two independent loads over a 10 mm to 42 mm single-link distance. The chip fabricated in standard 65 nm CMOS occupies 0.2 mm$^2$ active area and its performance is validated through In-vivo experiments.