Abstract
A wide-dynamic range high-efficiency differential RF-to-DC power converter for wireless power transfer (WPT) applications is presented. The architecture offers high power conversion efficiency (PCE) over a wide range of input powers by employing cross-coupled high-threshold rectifying devices with stacking diodes. The proposed rectifier uses the adaptive biasing technique to control the rectifying devices' conduction and minimizes the leakage current of the feedback diodes by utilizing the dynamic body biasing. Compared to the conventional cross-coupled rectifier, the proposed rectifier has a 9.4 x better dynamic range. A prototype of the proposed rectifier is implemented in 65-nm CMOS technology and occupies an area of 0.0148 mm(2). The rectifier achieves -18.1 dBm sensitivity for 1V output and a 79.4% peak PCE. A dynamic range of 17.3dB is achieved at the 433 MHz in the Industrial Scientific Medical band (ISM band) with a 100-K Omega load. Furthermore, the proposed design offers a peak PCE of 62.6% and a wide dynamic range of 16.1 dB at the UHF 900 MHz band with a load resistance of 100-K Omega.