无源超高频RFID低压高效电荷泵的设计与实现

提出了一种适用于无源超高频射频识别(RFID)标签的低压高效电荷泵电路的设计方案，用以最大化标签的识别距离。该方案利用偏置电路为主电荷泵提供偏置电压，通过二极管连接的MOSFET抑制偏置电路的负载电流来提高偏置电压，大大减小了传统电荷泵中的阈值损失，有效抑制了反向漏电流，提高了电荷泵的灵敏度和能量转换效率。该结构使用chartered 0.35 μm CMOS工艺进行流片验证，实测结果表明，在输入275 mV负载电阻200 kΩ情况下，电荷泵输出可达1.47 V，能量转换效率最高可达26.2%；采用该电荷泵的RFID标签识别距离最远可达4.2 m。该设计为RFID芯片的良好性能提供了可靠保证。

Design and Implementation of a Low Voltage High Efficiency Charge Pump for Passive UHF RFID

A low voltage high efficiency charge pump circuit for passive UHF RFID is presented to increase the operating range of tags. The bias voltage supplied to the main charge pump by the bias circuit is raised by suppressing its load current using a diode connected MOSFET, which greatly reduces the threshold voltage drop in traditional charge pumps, suppresses the reverse leakage current and improves the sensitivity and power conversion efficiency. The charge pump has been fabricated in chartered 0.35 μm CMOS process. Measurement results show that a 275 mV minimum input level is required to generate 1.47 V power supply for 200 kΩ load and efficiency up to 26.2% is achieved. The maximum operating range of the RFID tag with this charge pump is 4.2 m. This design effectively contributes to the good performance of RFID chips.