The LTC3713 is a high current, high efficiency synchronous buck switching regulator controller optimized for use with very low input supply voltages. It operates from inputs as low as 1.5V and provides a regulated output voltage from 0.8V up to (0.9)VIN. The controller uses a valley current control architecture to enable high operating frequencies without requiring a sense resistor.Operating frequency is selected by an external resistor and is compensated for variations in VINand VOUT. The LTC3713 uses a pair of standard 5V logic-level N-channel external MOSFETs, eliminating the need for expensive P-channel or low threshold devices.Discontinuous mode operation provides high efficiency operation at light loads. A forced continuous control pin reduces noise and RF interference, and can assist secondary winding regulation by disabling discontinuous operation when the main output is lightly loaded. Fault protection is provided by internal foldback current limiting,an output overvoltage comparator and an optional short-circuit shutdown timer.ApplicationsTelecom Card 3.3V, 2.5V, 1.8V Step-DownBus Termination (DDR memory, SSTL)Synchronous Buck with General Purpose BoostLow VINSynchronous Boost