The LTC3609 is a high efficiency, monolithic synchronous step-down DC/DC converter that can deliver up to 6A output current from a 4V to 32V (36V maximum) input supply. It uses a valley current control architecture to deliver very low duty cycle operation at high frequency with excellent transient response. The operating frequency is selected by an external resistor and is compensated for variations in VIN and VOUT. The LTC3609 can be configured for discontinuous or forced continuous operation at light load. Forced continuous operation reduces noise and RF interference while discontinuous mode provides high efficiency by reducing switching losses at light loads. Fault protection is provided by internal foldback current limiting, an output overvoltage comparator and an optional short-circuit shutdown timer. Soft-start capability for supply sequencing is accomplished using an external timing capacitor. The regulator current limit is user programmable. A power good output voltage monitor indicates when the output is in regulation. The LTC3609 is available in a compact 7mm × 8mm QFN package.
