LTC4080X Datasheet | Linear Technology

500m A Standalone Li-Ion Charger with Integrated 300m A Synchronous Buck in 3mm × 3mm DFN Features Description nn plete Linear Battery Charger with Integrated Buck Converter in 3mm x 3mm DFN Package Battery Charger: nn Constant-Current/Constant-Voltage Operation with Thermal Feedback to Maximize Charge Rate Without Risk of Overheating nn Internal 4.5 Hour Safety Timer for Termination nn Charge Current Programmable Up to 500m A with 5% Accuracy nn C/10 Charge Current Detection Output nn 5µA Supply Current in Shutdown Mode Switching Regulator: nn High Efficiency Synchronous Buck Converter nn 300m A Output Current (Constant-Frequency Mode) nn 2.7V to 4.5V Input Range (Powered from BAT Pin) nn 0.8V to VBAT Output Range nn MODE Pin Selects Fixed (2.25MHz) Constant-Frequency PWM Mode or Low ICC (23µA) Burst Mode® Operation nn 2µA BAT Current in Shutdown Mode Applications nn Wireless Headsets nn Bluetooth Applications nn Portable MP3 Players nn Multifunction Wristwatches The LTC®4080X is a plete constant-current/constantvoltage linear battery charger for a single-cell 4.2V lithium-ion/polymer battery with an integrated 300m A synchronous buck converter. A 3mm × 3mm DFN package and low external ponent count make the LTC4080X especially suitable for portable applications. Furthermore, the LTC4080X is specifically designed to work within USB power specifications. The CHRG pin indicates when charge current has dropped to ten percent of its programmed value (C/10). An internal 4.5 hour timer terminates the charge cycle. The full-featured LTC4080X battery charger also includes automatic recharge and soft-start to limit inrush current. If trickle charging is desired, please see the LTC4080 data sheet. The LTC4080X integrates a synchronous buck converter that is powered from the BAT pin. It has an adjustable output voltage and can deliver up to 300m A of load current. The buck converter also Features low-current high-efficiency Burst Mode operation that can be...