Vertical LLC Converter for High-Current Datacenter Application

Efficient and compact switched-mode power supplies are desired in the industry. In this paper, a novel transformer array is presented, composed of simple transformer cells. By employing four of these cells with primary windings in series, a 40 V-5 V LLC converter operating at 1 MHz is designed and implemented for high-current datacenter applications. The peak output power of the prototype is 520 W. Accordingly, the power density is 775 W/inch³ excluding the volume of connectors. The highest efficiency reaches 95.9% at an output power of 210 W.