SLVT248 May 2026 – May 2026
This reference design is a 48W, low-profile DC/DC auxiliary power supply targeting server PSU applications. The design features an integrated flyback controller with a Gallium Nitride (GaN) power switch. The design achieves a height of less than 10mm by utilizing a low-profile planar printed circuit board (PCB) transformer, meeting the high power density requirements of modern server PSU applications. The flyback converter UCG28824 incorporates VCC self-bias functionality, which simplifies the planar transformer PCB winding design by eliminating the need for auxiliary windings and associated VCC rectifier circuity. This supply operates using the PFC bus voltage as an input, and generates two isolated 12V/3A, 24V/0.1A outputs and a non-isolated 18V/0.5A output.