New EPC GaN FET targets AI and advanced computing
1 kW,  48V/12V LLC converter features 5130 W/in3 power density 
EPC has announced a 48V/ 12 V, LLC converter designed for high-density 48V server power and DC-DC converters. 
The EPC9159 reference design can deliver 1kW of power in a tiny 17.5 mm x 22.8 mm footprint for a power density of 5130 W/cm3. This is achieved by employing GaN power switches operating at high switching frequencies in both the primary and secondary circuits.
The power supply topology used in the design of the EPC9159 is based on the LLC topology. The implemented LLC consists of a primary side full bridge, a fixed ratio planar transformer, and a centre tab synchronous rectifier for the secondary side.  The primary full bridge uses four EPC2619, 80V-rated 3.3 mΩ GaN transistors, and the secondary uses six EPC2067, 40V-rated 1.3mΩ GaN transistors. 
The EPC9159 achieves a power stage efficiency of 98 percent at 25A and a full-load efficiency of 96.2 percent at 83A into 12V.  This design is ideal for high-density computing applications such as AI and advanced gaming. 
“eGaN FETs and ICs provide the fast switching, small size, and high efficiency needed to provide the highest power density solutions for advanced computing applications,” said Alex Lidow, CEO of EPC. “The EPC9159 is the ideal solution to address the growing power needs of AI and to support the transition to 48V input for the new high density and high efficiency servers required for these advanced computing applications.”