Micropower Buck Regulator with Integrated Boost and Catch Diodes

DESCRIPTIO

The LT® 3470 is a micropower step-down DC/DC converter that integrates a 300mA power switch, catch diode and boost diode into a low profile (1mm) ThinSOTTM package. The LT3470 combines Burst Mode and continuous operation to allow the use of tiny inductor and capacitors while providing a low ripple output to loads of up to 200mA. With its wide input range of 4V to 40V, the LT3470 can regulate a wide variety of power sources, from 2-cell Li-Ion batteries to unregulated wall transformers and leadacid batteries. Quiescent current in regulation is just 26µA in a typical application while a zero current shutdown mode disconnects the load from the input source, simplifying power management in battery-powered systems. Fast current limiting and hysteretic control protects the LT3470 and external components against shorted outputs, even at 40V input.