LTC4080X - 500mA Standalone Li-Ion Charger with Integrated 300mA Synchronous Buck

The LTC4080X is a complete constant-current / constant-voltage linear battery charger for a single-cell 4.2V lithium-ion/polymer battery with an integrated 300mA synchronous buck converter. A 3mm × 3mm DFN package and low external component 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 datasheet.

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 300mA of load current. The buck converter also features low-current high-efficiency Burst Mode operation that can be selected by the MODE pin.

The LTC4080X is available in 10-lead, low profile (0.75 mm) 3mm × 3mm DFN and 10-lead MSE packages.

Features

Complete Linear Battery Charger with Integrated Buck Converter
Available in 10-lead, low profile (0.75 mm) 3mm × 3mm DFN and 10-lead MSE packages Battery Charger:
Constant-Current/Constant-Voltage Operation with Thermal Feedback to Maximize Charge Rate Without Risk of Overheating
Internal 4.5 Hour Safety Timer for Termination
Charge Current Programmable Up to 500mA with 5% Accuracy
C/10 Charge Current Detection Output
5µA Supply Current in Shutdown Mode Switching Regulator:
High Efficiency Synchronous Buck Converter
300mA Output Current (Constant-Frequency Mode)
2.7V to 4.5V Input Range (Powered from BAT Pin)
0.8V to VBAT Output Range
MODE Pin Selects Fixed (2.25MHz) Constant
Frequency PWM Mode or Low ICC (23µA) Burst Mode® Operation
2µA BAT Current in Shutdown Mode