Current-mode controlled single-inductor dual-output buck converter with ramp compensation

Abstract

Sub-harmonic oscillation is a key factor causing instability for current-mode controlled single-inductor dual-output (SIDO) Buck converter. To inhibit the sub-harmonic oscillation of the converter and to extend its stable operating range, the ramp compensation technique is introduced in this paper. The discrete iterative map model of current-mode controlled SIDO Buck converter with ramp compensation is established at first. Then, the bifurcation behavior and Lyapunov exponent of the converter are emphatically studied based on the discrete iterative map. Finally, comparison frame-work is carried out based on the experiments of current-mode controlled SIDO Buck converter with and without ramp compensation unit to certificate the theoretical analysis results.