The LT®3972 is an adjustable frequency (200kHz to 2.4MHz) monolithic buck switching regulator that accepts input voltages up to 33V (62V Maximum). A high effi ciency 95mΩ switch is included on the die along with a boost Schottky diode and the necessary oscillator, control, and logic circuitry. Current mode topology is used for fast transient response and good loop stability. Low ripple Burst Mode operation maintains high effi ciency at low output currents while keeping output ripple below 15mV in a typical application. In addition, the LT3972 can further enhance low output current effi ciency by drawing bias current from the output when VOUT is above 3V. Shutdown reduces input supply current to less than 1μA while a resistor and capacitor on the RUN/SS pin provide a controlled output voltage ramp (soft-start). A power good fl ag signals when VOUT reaches 91% of the programmed output voltage. The LT3972 is available in 10-Pin MSOP and 3mm × 3mm DFN packages with exposed pads for low thermal resistance.