Ultra-high Power Density Server Supplies Employing GaN Power Semiconductors and PCB-Integrated Magnetics

The trend towards higher computation power per server rack has lead to an increased interest in high density server power supplies with high efficiency and low cost. This paper analyzes how the specific features of planar magnetics as transformers and inductors can be best utilized in combination with GaN power semiconductors to reach unprecedented system performance both for power supplies with 12V and with 48V output voltage. Based on the optimization results a hardware demonstrator with an ultra-high power density (350W/in3) of a 3kW DC/DC converter stage with a wide-input voltage range of 300V-430V and an output voltage of 12V is presented.