题目/Title：
                        A Current-mode Voltage Regulator with Sub-threshold Voltage Reference for Passive UHF RFID Tag

作者/Author：刘忠奇,张春,李永明,王志华
                        Zhongqi Liu,Chun Zhang,Yongming Li,Zhihua Wang

期刊/Journal：半导体学报 Chinese Journal of Semiconductors

年份/Issue Date：2010

卷（期）及页码/Volume（No.）&pages：Vol.31, No.6, pp. 065006 - 1 - 4

摘要/Abstract：

This paper presents a current mode voltage regulator for a passive UHF RFID tag. The passive tag power is extracted from RF energy through the RF-to-DC rectifier. Due to huge variations of the incoming RF energy, the rectifier output voltage should be regulated to achieve a stable power supply. The output voltage of the proposed regulator is clamped at 1.2V by an exact control of the rectified current flowing through the load. The current to the load is below 35μA, and can be adjusted by comparing the output voltage with an internal sub-threshold reference. The regulator is implemented in UMC 0.18µm mixed-mode CMOS technology. The simulation results show the regulated voltage variation is less than 14mV over a range from 0 to 40℃ with 35μ-6mA input current and 2-20μA load current. The entire current consumption of the regulator is only 0.9μA.