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Wide voltage range converters are significant for photovoltaic power generation system, battery charging, and auxiliary power source, etc. Resonant converter has been preferred topology for these applications, however, some demerits exist: 1) difficult to realize wide voltage gain range and low circulating current losses; 2) widely regulated switching frequency to adapt to wide voltage gain range; and 3) poor regulation at light load. Based on abovementioned shortcomings, dual resonance core-based step-up/down switched capacitor converter topology is presented in this article. Utilizing hybrid control strategy, nonoverlapping control strategy is used in the buck-type mode and overlapping control strategy is applied in the boost-type mode with common switching frequency range, and therefore, reduced frequency range in the presented converter is achieved. Moreover, wide voltage gain range can be obtained due to step-up/down capacity in the proposed converter. Furthermore, conversion ratio of proposed converter can be reduced to zero theoretically by using dual resonance core existed in the resonant switched capacitor converter. Finally, comprehensive operational principle analysis and performance analysis are provided, and a 48 to 28−90 V/100-W prototype is built to verify the analysis.

Single-inductor dual-output (SIDO) dc–dc converter has been applied to light-emitting diode (LED) drivers with its advantages of small volume and low cost. Peak-current-mode (PCM) control of the SIDO converter has the advantages of fast transient performance and suppressed cross-regulation. A PCM-controlled SIDO buck LED driver to achieve independent dimming and to eliminate the steady-state cross-regulation is proposed in this article. The circuit and the principle of the PCM-controlled SIDO buck LED driver are presented, and its small signal model is established based on inductor current ripple. Furthermore, based on control-to-output loop gain transfer functions, control parameters of PCM-controlled SIDO buck LED driver are designed to achieve independent output current regulation of each LED driver. Besides, cross-regulation transfer functions are obtained to investigate the effect of reference signals and control parameters on the transient cross-regulation. Moreover, the effect of capacitor parameters on the stability of the LED driver is analyzed based on the bifurcation diagram. Finally, experimental results are provided to show the independent dimming capability of PCM-controlled SIDO buck LED driver with designed parameters, and the validity of the theoretical analysis on transient cross-regulation and stability of the LED driver.