Dual Inductor Hybrid Converter for Point-of-Load Voltage Regulator Modules

Achieving high-efficiency power conversion with high power density for a large conversion ratio is crucially needed yet challenging in point-of-load applications because of increasing demands of loads. This article presents a new hybrid converter to address this need. The converter uses two interleaved inductors for complete soft charging of flying capacitors to provide high output currents with no capacitor hard-charge loss. This dual inductor hybrid (DIH) converter features a smaller number of switches and more effective switch utilization than a recently reported hybrid Dickson converter, yielding substantially less switch losses represented by smaller volt–ampere products and smaller equivalent output resistance. Converter operation principle is analyzed in detail to confirm the feasibility and benefits, and design considerations are provided to identify a practical design process. Experimental results verify the converter's operation principles and advantages with a 300-kHz 20-W prototype achieving 95.02% peak efficiency and 225-W/in3 power density. The converter's advantages and performance make the point-of-load converter architecture a good candidate for demanding applications, such as in data centers, telecommunications, and high-performance digital systems.

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