The TP4057 is a complete linear charger for single cell lithium-ion batteries. This chip with reverse battery protection and power supply reverse connect protection. Its SOT23-6 package and low external component count make the TP4057 ideally suited for portable applications. Furthermore, the TP4057 can work within USB and wall adapter.

Thermal feedback regulates the charge current to limit the die temperature during high power operation or high ambient temperature. Full charge voltage is fixed at 4.2V, and the charge current can be programmed externally with a single resistor. The TP4057 automatically terminates the charge cycle when the charge current drops to 1/10th the programmed value after the final float voltage reaching.

 - Programmable charging current up to 500mA

 - No MOSFET, sense resistor or isolating diode required

 - Lithium-ion batteries Reverse battery protection

 - Maximize Charge Rate Without Risk of Overheating

 - For Single Cell titanic acid Lithium-Ion Batteries

 - Constant-current and constant-voltage control 

 - Charges Single Cell Li-Ion Batteries Directly from USB Port

 - Preset Charge Voltage with 1% Accuracy

 - Highest input can be up to 9V

 - Automatic Recharge

 - Two Charge Status Output Pins

 - C/10 Charge Termination

 - 40uA Supply Current in Shutdown

 - Available in 6-Lead SOT-23 Package