The ADP3171 is a highly efficient output synchronous buck switching regulator controller optimized for converting a 5 V main supply into the auxiliary supply voltages required by processors and chipsets. The ADP3171 provides a fixed output voltage of 1.2 V at up to 15 A, depending on the power ratings of the external MOSFETs and inductor. The ADP3171 uses a current-mode, constant off time architecture to drive two N-channel MOSFETs at a programmable switching frequency that can be optimized for regulator size and efficiency.