A Triple-Mode Wireless Power-Receiving Unit With 85.5% System Efficiency for A4WP, WPC, and PMA Applications

Abstract

This paper presents the design of a triple-mode wireless power-receiving unit (TWPRU) for battery charger with high efficiency. The TWPRU is proposed based on Alliance for Wireless Power (A4WP), Wireless Power Consortium (WPC), and Power Matters Alliance (PMA) standards. An adaptive alignment gate controller technique is proposed in the triple-mode active rectifier to block the reverse leakage current and improve the power conversion efficiency (PCE). This technique can compensate for the delays in the gate control signals of the main switching MOSFETs at different operating frequencies for A4WP, WPC, and PMA. The dead time of a dc-dc converter is optimally determined depending on the voltage and the temperature variations by phase calibration circuit. This chip with an active area of 5.0 mm x 3.5 mm is implemented in 0.18-mu m BCD technology. The maximum PCEs of the triple-mode active rectifier are 91.7% in the A4WP mode and 92.7% in the WPC/PMA mode, respectively. The maximum PCE of the dc-dc converter is 92.3% at a load current of 500 mA, while the system efficiencies of TWPRU at A4WP and WPC/PMA modes are about 84.5% and 85.5%, respectively.