LTC4065L-4.1 Datasheet | Linear Technology

FEATURES nn Charge Current Programmable up to 250m A with 5% Accuracy nn plete Linear Charger in 2mm × 2mm DFN Package nn C/10 Charge Current Detection Output nn Timer Termination nn No External MOSFET, Sense Resistor or Blocking Diode Required nn Preset Float Voltage with 0.6% Accuracy: 4.2V for LTC4065L/LTC4065LX 4.1V for LTC4065L-4.1/LTC4065LX-4.1 nn Constant-Current/Constant-Voltage Operation with Thermal Feedback to Maximize Charging Rate Without Risk of Overheating nn Charge Current Monitor Output for Gas Gauging nn Automatic Recharge nn Charges Single Cell Li-Ion Batteries Directly from USB Port nn 20µA Supply Current in Shutdown Mode nn Available Without Trickle Charge (LTC4065LX/ LTC4065LX-4.1) nn Tiny 6-Lead (2mm × 2mm) DFN Package APPLICATIONS nn Charger for Li-Ion Coin Cell Batteries nn Portable MP3 Players, Wireless Headsets nn Bluetooth Applications nn Multifunction Wristwatches All registered trademarks and trademarks are the property of their respective owners. Protected by U.S. Patents, including 6522118, 6700364. DESCRIPTION The LTC®4065L is a plete constant-current/constantvoltage linear charger for single-cell lithium-ion batteries. Its small size and ability to accurately regulate low charge currents make the LTC4065L especially well-suited for portable applications using low capacity rechargeable lithium-ion cells. Furthermore, LTC4065L 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 timer terminates charging according to battery manufacturer specifications. The LTC4065L-4.1/LTC4065LX-4.1 features a constantvoltage float voltage of 4.1V. This 4.1V version of the standard LTC4065L/LTC4065LX is intended for back-up or high ambient temperature applications. Under these conditions, a reduced float voltage will trade-off initial cell capacity for the benefit of increased capacity retention over the life of the battery....