The Design of the Singe-Inductor Dual-Outputs DC-DC Buck Converter Based on the Capacitor-Charge-Balance and the Variable-Frequency-Control Method

Abstract

In this paper, a new method called the Capacitor-Charge-Balance and the Variable-Frequency-Control (CCB-VFC) for a single-inductor dual-outputs (SIDO) buck converter is proposed to achieve the fast-transient response and the low cross-regulation. A SIDO buck converter operating at continuous conduction mode (CCM) is taken as an example to analyze the operation when the load current steps up. The proposed method makes the unchanged load operate at the steady-state during the transient process to suppress the cross-regulation while the inductor current rises to a new steady-state rapidly to achieve the fast response. In order to verify the performance of the proposed method, simulation platform is built in the MATLAB/Simulink environment. Simulation results demonstrate that the CCB-VFC method guarantees the low cross-regulation for the SIDO buck converter in continuous conduction mode (CCM) and improves the transient performance.