DESCRIPTION
The LTC®3539/LTC3539-2 are synchronous, 2A step-up DC/DC converters with output disconnect. Synchronous rectification enables high efficiency in the low profile 2mm × 3mm DFN package. Battery life is extended with a 700mV start-up voltage and operation down to 500mV once started.

FEATURES
■ Delivers 3.3V at 900mA From 2 Alkaline/NiMH Cells
■ Delivers 5V at 900mA From a Lithium-Polymer Battery
■ VIN Start-Up Voltage: 700mV
■ 1.5V to 5.25V VOUT Range
■ Up to 94% Efficiency
■ VIN > VOUT Operation
■ ±1.5% Feedback Voltage Tolerance
■ 1MHz (LTC3539) or 2MHz (LTC3539-2) Fixed Frequency Operation
■ Output Disconnect
■ Selectable Burst Mode® or PWM Operation
■ 10µA Quiescent Current
■ Logic Controlled Shutdown: <1µA
■ Requires Only 6 External Components
■ Low Profile (2mm × 3mm × 0.75mm) DFN Package

APPLICATIONS
■ Medical Instruments
■ Portable Bar Code Scanners
■ Noise Canceling Headphones
■ Portable GPS Navigation
■ Handheld PCs