Abstract: This paper presents a low voltage,low power RF/analog front-end circuit for passive ultra high frequency (UHF) radio frequency identification (RFID) tags.Temperature compensation is achieved by a reference generator using sub-threshold techniques.The chip maintains a steady system clock in a temperature range from -40 to 100℃.Some novel building blocks are developed to save system power consumption,including a zero static current power-on reset circuit and a voltage regulator.The RF/analog front-end circuit is implemented with digital base-band and EEPROM to construct a whole tag chip in 0.18μm CMOS EEPROM technology without Schottcky diodes.Measured results show that the chip has a minimum supply voltage requirement of 0.75V.At this voltage,the total current consumption of the RF/analog front-end circuit is 4.6μA.

Key words: RFID,  tag,  low voltage,  low power,  temperature compensation