Features

• Low Quiescent Current: 35μA at 12V_IN to 3.3V_OUT
• Integrated Boost and Catch Diodes
• Input Range: 4V to 40V
• 3.3V at 250mA from 4V to 40V Input
• 5V at 250mA from 5.7V to 40V Input
• Low Output Ripple: <10mV
• <1μA in Shutdown Mode
• Output Voltage: 1.25V to 16V
• Hysteretic Mode Control
  – Low Ripple Burst Mode® Operation at Light Loads
  – Continuous Operation at Higher Loads
• Solution Size as Small as 50mm²
• Low Profile (0.75mm) 2mm × 3mm Thermally Enhanced 8-Lead DFN Package

Typical Application

Description

The LT3470A is a micropower step-down DC/DC converter that integrates a 440mA power switch, catch diode and boost diode into low profile 2mm × 3mm DFN package. The LT3470A 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 250mA.

With its wide input range of 4V to 40V, the LT3470A can regulate a wide variety of power sources, from 2-cell Li-Ion batteries to unregulated wall transformers and lead-acid batteries. Quiescent current in regulation is just 35μA 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 LT3470A and external components against shorted outputs, even at 40V input. The LT3470A has higher output current and improved start-up and dropout performance compared to the LT3470.