
Linear Technology
DESCRIPTION
The LTC® 4054L is a complete, constant-current/constant voltage linear charger for single cell lithium-ion batteries. Its small size and ability to regulate low charge currents make the LTC4054L especially well-suited for portable applications using low capacity rechargeable lithium-ion coin cells. Furthermore, the LTC4054L is specifically designed to work within USB power specifications.
FEATURES
■ Programmable Charge Current Range: 10mA to 150mA
■ No External MOSFET, Sense Resistor or Blocking Diode Required
■ Complete Linear Charger in ThinSOT™ Package for Single Cell/Coin Cell Lithium-Ion Batteries
■ Constant-Current/Constant-Voltage Operation with Thermal Regulation* to Maximize Charge Rate Without Risk of Overheating
■ Charges Single Cell Li-Ion Batteries Directly from USB Port
■ Preset 4.2V Charge Voltage with ±1% Accuracy
■ Charge Current Monitor Output for Gas Gauging*
■ Automatic Recharge
■ Charge Status Output Pin
■ C/10 Charge Termination
■ 25µA Max Supply Current in Shutdown Mode
■ 2.9V Trickle Charge Threshold
■ Soft-Start Limits Inrush Current
■ Available in a 6-Lead Low Profile (1mm) SOT-23 Package
APPLICATION
■ Charger for Li-Ion Coin Cell Batteries
■ Portable MP3 Players, Wireless Headsets
■ Bluetooth Applications
■ Multifunction Wristwatches