Modeling and Analysis of Voltage Ripple-Controlled SIDO Buck Converter in Pseudo-Continuous Conduction Mode with Limited Cross-Regulation and Fast Load Transient Performance

Abstract

Typical voltage mode-controlled DC–DC converters with single-inductor dual-output (SIDO) in pseudo-continuous conduction mode (PCCM) have slow load transient performance, and cross-regulation still exists between their two outputs. For the purposes of suppressing the cross-regulation and improving the load transient performance, a voltage ripple control technique for a PCCM SIDO buck converter is proposed in this study. A description of the PCCM SIDO buck converter and the voltage ripple control technique is provided in detail. In addition, the small-signal model was established, and the cross-regulation was further compared by Bode plots, as well as the load range and the power losses being analyzed. The cross-regulation and load transient performance of the voltage ripple-controlled PCCM SIDO buck converter was studied and compared with the conventional voltage mode-controlled. Using the proposed voltage ripple control for PCCM SIDO buck converters, we found no cross-regulation or rapid load transient behavior, which was validated by experimental results.