The LT3970 is an adjustable frequency monolithic buck switching regulator that accepts a wide input voltage range up to 40V, and consumes only 2.5A of quiescent current. A high efficiency switch is included on the die along with the catch diode, boost diode, and the necessary oscillator, control and logic circuitry. Low ripple Burst Mode operation maintains high efficiency at low output currents while keeping the output ripple below 5mV in a typical application. Current mode topology is used for fast transient response and good loop stability. A catch diode current limit provides protection against shorted outputs and overvoltage conditions. An enable pin with accurate threshold is available, producing a low shutdown current of 0.7A. A power good flag signals when VOUT reaches 90% of the programmed output voltage. The LT3970 is available in small 10-pin MSOP and 3mm x 2mm DFN packages.