A Speed and Accuracy Enhanced Current Sensor for Buck Converter

A fast-response and high-accuracy novel current sensor applied for converter is presented in this paper. Dynamic bias feedback technology is applied in the amplifier to improve the speed and stability of the current sensor under a wide range of load currents. A shunt circuit and a current compensation circuit are implemented to enhance sensing accuracy. The proposed current sensor is designed based on a standard 0.15-µm CMOS process. The simulation results show that the proposed current sensor offers fast responsiveness with a response time under 22 ns. With load current ranging from 100mA-2A, the current sensing accuracy can achieve 99.77%.