A High-Efficiency CMOS Rectifier for RF Using Bulk Biasing Control Circuit
Keywords:CMOS rectifier; bulk biasing; power conversion efficiency
In MOSFET-transistor based rectifier circuits, leakage currents occur through both source-bulk and drain-bulk connections of their transistors causing some power dissipation decreasing their efficiency. Such a scenario is more worrying in ultra-low power circuits as those used in energy harvesting. As a solution, in this work it is proposed a control circuit of transistor bulk biasing that switches the bulk bias in an efficient way assuring adequate inversion of the source-bulk and drain-bulk junctions. The rectifier based on the proposed bulk biasing control circuit shows to be a high-efficiency one capable of reducing the leakage currents. To obtain experimental results, the circuit was fabricated in a 130 nm CMOS process and tested on a micromanipulator. The results were compared with other works where it is observed that the efficiency of our proposal reaches up to 72.5% or 5% higher that the best previous one.