
Linear Technology
DESCRIPTION
The LTC®3455/LTC3455-1 are complete power management solutions for a variety of portable applications. These devices contain two synchronous step-down DC/DC converters, a USB power controller, a full-featured Li-Ion battery charger, a Hot Swap output, a low-battery indicator, and numerous internal protection features. The LTC3455/LTC3455-1 provide a small, simple solution for obtaining power from three different power sources: a single-cell Li-Ion battery, a USB port, and a wall adapter
FEATURES
■ Seamless Transition between Input Power Sources:
Li-Ion Battery, USB, and 5V Wall Adapter
■ Accurate USB Current Limiting (500mA/100mA)
■ Two High Effi ciency DC/DC Converters: Up to 96%
■ Thermal Regulation Maximizes Battery Charge
Rate without Risk of Overheating
■ Full-Featured Li-Ion Battery Charger with 4.2V Float
Voltage for LTC3455 and 4.1V for LTC3455-1
■ 4.1V Float Voltage (LTC3455-1) Improves Battery Life
and High Temperature Safety Margin
■ Hot Swap™ Output for SDIO and Memory Cards
■ Pin-Selectable Burst Mode® Operation
■ Output Disconnect: All Outputs Discharged to Ground
During Shutdown
■ Available in a 4mm × 4mm × 0.75mm 24-Pin
QFN Package
APPLICATIONS
■ Handheld Computers
■ Digital Cameras
■ MP3 Players