High Efficiency Secondary Side Synchronous Buck PWM Controller

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-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 Drive™ technology that virtually eliminates body diode conduction losses in synchronous rectifiers.

The UCC2540 is available in the extended temperature range of –40°C to 105°C and is offered in thermally enhanced PowerPAD™ 20-pin HTSSOP (PWP) package. This space saving package with standard 20-pin TSSOP footprint has a drastically lower thermal resistance of 1.4°C/W øJC to accommodate the dual high-current drivers on board.