A low-input-swing AC-DC voltage multiplier using Schottky diodes

A low-input-swing AC-DC voltage multiplier using Schottky diodes is presented. The equivalent model of the voltage multiplier is developed and analyzed. To enhance power conversion efficiency (PCE), a matching network is added. For a multiple-stage voltage multiplier, a limiting circuit is added for over-voltage protection. A single-stage/three-stage voltage multiplier with a limiting circuit is fabricated in a 0.18μm CMOS technology and its area is equal to 0.761mm². With the matching network, the measured maximum PCE are 31.4% and 35.8% when input amplitudes are 60mV and 160mV for a single-stage voltage multiplier and a three-stage one, respectively, at input frequency of 1MHz.