The UCC2540 is a secondary-side synchronous buck PWM controller for high current and low output voltage applications. It can be used either as the local secondary-side controller for isolated dc-to-dc converters using two-stage cascaded topologies or as a secondary-side post regulator (SSPR) for multiple output power supplies. The UCC2540 runs with the synchronization signal from either the primary side or the high duty cycle quasi-dc output of bus converters or dc transformers. For higher efficiency, it also incorporates the Predictive Gate Drivet technology that virtually eliminates body diode conduction losses in synchronous rectifiers.