An 87% Efficient Wireless Powered System Using Adaptively Controlled Active Rectifier for Smart Electronics

This brief presents an efficient wireless powered system (WPS) for smart electronics, including battery charging. To enhance the performance of WPS, we have utilized an adaptively-controlled active rectifier matrix (AARM) that helps to regulate the output voltage over a wide-range load variation. In addition, we propose a digital compensation circuit that adjusts both turn-on and turn-off times to compensate for delays of the comparator when it turns off and on. The proposed WPS is implemented in a 0.18 mu m high-voltage Bipolar-CMOS-DMOS(BCD) process. The WPS can achieve 270 mW of the peak (a) power while flowing 135 mA of the load current. The measured peak conversion efficiency is S7% at 0. 89mW of the output power.