A On-Chip Current Sensing Circuit for Boost Converter

A new on-chip current sensing circuit for DC-DC boost converter is present in this paper. The proposed scheme is base on SENSEFET technique, compensating the bias current to acquire high accuracy and using an improved common-gate amplifier to get high speed; the circuit can save chip area and reduce power consumption as eliminating the need for operational amplifiers. The performance of the circuit is simulated with Cadence Spectre in a 0.35 micrometer 40V BCD process, and the accuracy is above 96.7% for the load current from 200mA to 1.5A, it is suitable for high power boost DC-DC converter.