Integrated zero-inductor-current detection circuit for step-up DC-DC converters

Abstract

A new integrated zero-inductor-current detection circuit suitable for step-up DC-DC converters is presented. The detection circuit can correctly detect zero-inductor-current with a novel method. The method helps overcome difficulties in measuring online current from on-resistance of output PMOS switches. With its simplicity and independence from output PMOS switches, this circuit promises wide application in either single-output step-up DC-DC converters or single inductor multiple output (SIMO) step-up DC-DC converters with different control theories, and especially in discontinuous-conduction-mode (DCM) operation.