High Efficiency CLL Resonant Converter with Synchronous Rectifier
The CLL resonant dc-dc converter (CLL) is an alternative option in off-line applications. This topology can achieve zero-voltage-switching (ZVS) from zero load to full load range, low circulating energy and zero-current-switching (ZCS) for output rectifiers.
The air gap of the CLL resonant converter transformer is omitted to eliminate fringing effect. Because of very high magnetizing inductance, the transformer primary side current is in phase with the secondary side current. Thus, SR can be easily driven. Moreover, resonant inductance is integrated with the transformer to reduce the passive component volume.