In the first part of this work, we review the design of fully-differential RF-DC rectifiers in the context of the design of CMOS passive UHF RFID transponder ICs. The results are applicable to the systems where the supply voltage is obtained by extracting ambient RF energy. The operation of the fully-differential rectifiers is explained starting from a simple diode-C rectifier circuit. It is shown that these rectifiers are extension of the basic rectifier circuit where the 2-terminal diodes are replaced by 3-terminal MOSFETs allowing the reduction of the voltage across the switches. We also reviewed the design of the cascaded multi-stage rectifiers from the perspective of a circuit design engineer to yield some design guidelines when designing such circuits.
Revolution Semiconductor, RF, Energy Harvesting