Integrated current-sensing circuit with offset-current cancellation for boost converters

A novel integrated CMOS current-sensing circuit suitable for boost dc-dc converters is presented in this paper. The proposed current-sensing circuit can cancel the offset-current in the traditional current-sensing circuit, thus a higher sensing-accuracy is achieved. Moreover the op-amp used as a voltage follower is not used in the proposed current-sensing circuit. Using a standard 0.6 mum CMOS process, the proposed current-sensing circuit has been designed. The performances of the proposed circuit with different duty-ratios are simulated. The simulation results verify the validity of the proposed circuit and its current-sensing accuracy.