Differential-drive CMOS rectifier with photovoltaic-assist and self-Vth-cancellation schemes for high power conversion efficiency under low input power conditions

Abstract

Abstract In this study, a differential-drive CMOS RF rectifier equipped with photovoltaic assistance and self-Vth-cancellation (SVC) mechanism has been developed for efficient energy harvesting from ambient radio waves. In addition to the differential-drive dynamic biasing, in which by dynamically biasing the MOSFET gates with differential input signal, both on-resistance and reverse leakage current of the MOSFET are reduced and high power conversion efficiency (PCE) can be achieved, the combination of SVC technology and photovoltaic assist technology allows further improvement of the PCE under low input power conditions. As a result, the PCE of 38.5% was achieved at an input power level of −22 dBm, a frequency of 1 GHz, an output load resistance of 10 kΩ, and a light irradiance of 1 W m−2.