DESCRIPTION
The LTC® 3407-3 is a dual, constant frequency, synchronous step down DC/DC converter. Intended for low power applications, it operates from 3.3V to 5.5V input voltage range and has a constant 2.25MHz switching frequency, allowing the use of tiny, low cost capacitors and inductors with a profile ≤1.0mm. Internal synchronous 0.35Ω, 1.2A power switches provide high efficiency without the need for external Schottky diodes.

FEATURES
■ Very Low Quiescent Current: Only 40µA
■ 1.8V at 800mA/3.3V at 800mA
■ High Efficiency: Up to 95%
■ 2.25MHz Constant Frequency Operation
■ High Switch Current: 1.2A on Each Channel
■ No Schottky Diodes Required
■ Low RDS(ON)Internal Switches: 0.35Ω
■ VIN: 3.3V to 5.5V
■ Current Mode Operation for Excellent Line and Load Transient Response
■ Short-Circuit Protected
■ Low Dropout Operation: 100% Duty Cycle
■ Ultralow Shutdown Current: IQ< 1µA
■ Power-On Reset Output
■ Externally Synchronizable Oscillator
■ Small Thermally Enhanced 3mm ×3mm DFN Package

APPLICATIONS
■ PDAs/Palmtop PCs
■ Digital Cameras
■ Cellular Phones
■ Portable Media Players
■ PC Cards
■ Wireless and DSL Modems