A high efficiency AC-DC charge pump using feedback compensation technique

Abstract

This paper presents a high performance AC-DC charge pump for RFID tags, with the self-bias feedback and threshold compensation technique. Compared with conventional charge pump, the influence of threshold is greatly reduced and output DC voltage and power conversion efficiency is greatly improved. This proposed charge pump with 5 stages is implemented in SMIC 0.18 mum standard CMOS process. Simulation and measurement results show that for sinusoidal wave (f = 3.56 MHz) with magnitude voltages of 0.5 V, 0.6 V, and 0.7 V the output DC voltages of 1.1 V, 1.5 V and 1.9 V can be generated respectively with 120 KOmega equivalent load. Measurement results show the power conversion efficiency (PCE) reaches as high as 36%. And the sensitivity performance of RFID tags is improved to as low as -14.5 dBm.