Features

• Small Solution Size
• >85% Efficiency over Wide Load Range
• Internal Synchronous Rectifier
• V_IN Range: 1.5V to 5.5V
• 5V at 30mA from 3.3V Input
• 3.3V at 20mA from 2 AA Cell Input
• Programmable Output Voltages Up to 10V
• Burst Mode Operation
• Inrush Current Limiting
• Output Disconnect in Shutdown
• Ultralow Quiescent (10µA) and Shutdown (<1µA) Currents
• Low Profile 2mm × 2mm DFN, 2mm × 3mm DFN or SOT-23 Package

Typical Application

Description

The LTC3459 is a low current, high efficiency synchronous boost converter intended for low power, size constrained portable applications. The LTC3459 can be powered from a single lithium ion battery, a 2- to 3-cell stack of Alkaline or Nickel batteries, or any low impedance voltage source between 1.5V and 5.5V. The output is programmable via an external divider between 2.5V and 10V. Although the part is primarily intended for boost applications, V_OUT will maintain regulation below V_IN (at reduced efficiency).

The LTC3459 offers Burst Mode operation with a fixed peak current, providing high conversion efficiency over a wide range of load currents. During start-up, inductor current is controlled preventing the inrush surge current found in many boost converters. In shutdown the output is disconnected from the input and quiescent current is reduced to <1µA.

The LTC3459 is offered in low profile 6-pin 2mm × 2mm DFN, 2mm × 3mm DFN or SOT-23 (ThinSOT) packages, allowing a tiny footprint for the total solution.