Automatic Correction of Current Imbalance due to Element Variations in Multi-Phase Ripple Controlled Converter

摘要

This paper describes multi-phase switching converters using the ripple control with the constant-on-time (COT) method. For the four-phase converter, four-phase clocks are generated by dividing the peak hold voltage by four which is supplied from the saw-tooth signal of the main converter. The single COT pulse generator is used for four sub-converters. This converter solves the problem of the current imbalance due to inductance and capacitance element variations for the large load current. For the two-phase converter, the COT pulse width is adjusted by detecting the current imbalance, so that good current balance is obtained.