Miniaturized modular power supplies hold considerable significance in domains such as telecommunications

automotive engineering

aerospace technology

and data processing systems.By elevating the operating frequency of circuits

the size of passive components can be diminished

thereby enhancing the system's overall power density.This paper explores a half-bridge LLC resonant converter configuration

delving into its fundamental working principles and distinctive characteristics while aligning system parameters with specific project requirements.Recognizing the effect of leakage inductance on the transformer's secondary side under high-frequency conditions

an optimized circuit model is proposed.To ensure soft-switching attributes

the parameter calculation methodology has been meticulously refined.A prototype leveraging Gallium Nitride （GaN）technology was developed for empirical validation.It delivers a rated output power of 300 W

operates at a switching frequency of 1 MHz

sustains a nominal input voltage of 48 V

and outputs a voltage of 12 V.The system achieves an efficiency of 95.6%at full load

substantiating the accuracy and reliability of the theoretical analysis presented herein.