A self biased full range current sensor for buck regulator

Abstract

A full range current sensor based on self-bias structure for buck regulator is presented in this paper. The proposed full range current sensor can sense current from both the high side and low side switches of the power regulator within the same switching cycle with input current varying from 50 mA to 500 mA. It has higher than 95% sensing accuracy while consuming less than 1% of the total input power. All the simulation results are based on 0.18μm CMOS process.