DN05124/D, 12V/6A Power over Ethernet Active-Clamp Forward DC-DC Converter

DN05124/D, Reference design provides elementary information about an active-clamp forward converter built with the NCP1566 operated in current-mode control. This controller offers many features to build an energy efficient converter with all the needed protections like cycle-by-cycle current limit with a 500-mV sense voltage, over current protection (OPP) for a stable maximum output current limit, over temperature protection with a dedicated NTC pin and a pin to sense an output voltage runaway (loop failure for instance). The controller drives a N-channel MOSFET as with any classical forward converter plus a P-channel for the active-clamp portion. A user adjustable deadtime is inserted to let the drain voltage fall sufficiently low to minimize switching losses. This controller can be configured to work in voltage or current-mode control