Ultra-low power analog front-end for passive UHF RFID tags

This paper presents an ultra-low power analog front-end circuit for passive UHF RFID tags. To improve power conversion efficiency, Schottky barrier diode based rectifier is adopted. The design of an area-efficient ASK demodulator with a novel average generator is discussed in detail. Most of the analog blocks are designed to work under sub-1v to reduce power consumption. The analog front-end circuit is implemented in 0.18?? m CMOS process. Measurement results show that with a 110k??resistor load, the power conversion efficiency of the rectifier reaches as high as 33.6%. The total power consumption of the analog front-end circuit is only 2.4?? W.EI