LTC3444 Datasheet | Linear Technology

LTC3444 Micropower Synchronous Buck-Boost DC/DC Converter for WCDMA Applications DESCRIPTIO The LTC®3444 is a highly efficient, fixed frequency, buckboost DC/DC converter, which operates from input voltages above, below, and 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 a single Lithium-Ion or multi-cell applications where the output voltage can vary over a wide range. The LTC3444 has been optimized for use in 3G WCDMA applications. A unique design yields high efficiency at very low output voltages while also eliminating external ponents. The high speed error amplifier provides the fast transient response required to slew the RF power amplifier from standby to transmit and transmit to stand by power levels. Output overvoltage protection protects the RF power amplifier. Operating frequency is internally set to 1.5MHz to minimize external ponent size while maximizing efficiency. Other Features include <1μA shutdown current, internal soft-start, peak current limit and thermal shutdown. The LTC3444 is available in a small, thermally enhanced 8-lead (3mm × 3mm) DFN package. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 6404251, 6166527. Features - - - - - - - - - - - - - - Optimized Features for WCDMA Handsets Regulated Output with Input Voltages Above, Below, or Equal to the Output 0.5V to 5V Output Range Up to 400m A Continuous Output Current From a Single Lithium-Ion Cell Minimal External ponents 1.5MHz Fixed Frequency Operation Internal Loop pensation for Fast Response <25μs Full Scale Output Slewing; COUT 4.7μF Output Disconnect in Shutdown 2.75V to 5.5V Input <1μA Shutdown Current Internal Soft-Start Output Overvoltage Protection Single Inductor, No Schottky Diodes Required Small, Thermally Enhanced...