摘要
This paper presents a passive UHF RFID tag with a dynamicVthcancellation (DVC) rectifier. In the rectifier, the threshold voltages of MOSFETs are cancelled by applying gate bias voltages, which are dynamically changed according to the states of the MOSFETs. The DVC rectifier enables both low ONresistance and small re verse leakage of the MOSFETs, resulting in high power conversion efficiency (PCE). An areaefficient demodulator with a novel average detector is also designed, which takes advantage of the rectifier's first stage as the envelope detector. The whole tag chip is implemented in a 0.18 μm CMOS process with a die size of 880 x 950μm2. Measurement results show that the rectifier achieves a maximum PCE of 53.7% with 80 kΩ resistor load.
This paper presents a passive UHF RFID tag with a dynamicVthcancellation (DVC) rectifier. In the rectifier, the threshold voltages of MOSFETs are cancelled by applying gate bias voltages, which are dynamically changed according to the states of the MOSFETs. The DVC rectifier enables both low ONresistance and small re verse leakage of the MOSFETs, resulting in high power conversion efficiency (PCE). An areaefficient demodulator with a novel average detector is also designed, which takes advantage of the rectifier's first stage as the envelope detector. The whole tag chip is implemented in a 0.18 μm CMOS process with a die size of 880 x 950μm2. Measurement results show that the rectifier achieves a maximum PCE of 53.7% with 80 kΩ resistor load.