
Linear Technology
DESCRIPTION
The LTC®3440 is a high efficiency, fixed frequency, Buck Boost DC/DC converter that operates from input voltages above, below or equal to the output voltage. The topology incorporated in the IC provides a continuous transfer function through all operating modes, making the product ideal for single lithium-ion, multicell alkaline or NiMH applications where the output voltage is within the battery voltage range.
FEATURES
■ Single Inductor
■ Fixed Frequency Operation with Battery Voltages Above, Below or Equal to the Output
■ Synchronous Rectification: Up to 96% Efficiency
■ 25μA Quiescent Current in Burst Mode® Operatio
■ Up to 600mA Continuous Output Current
■ No Schottky Diodes Required (VOUT < 4.3V)
■ VOUT Disconnected from VIN During Shutdown
■ 2.5V to 5.5V Input and Output Range
■ Programmable Oscillator Frequency from 300kHz to 2MHz
■ Synchronizable Oscillator
■ Burst Mode Enable Control
■ <1μA Shutdown Current
■ Small Thermally Enhanced 10-Pin MSOP and (3mm × 3mm) DFN Packages
APPLICATIONS
■ Palmtop Computers
■ Handheld Instruments
■ MP3 Players
■ Digital Cameras