BL4054

BL4054 800mA Standalone Linear Li-Ion Battery Charger with Thermal Regulation in Thin SOT FEATURES z DESCRIPTION The BL4054 is a complete constant-current / constant voltage linear charger for single cell Lithium-Ion batteries. No external sense resistor is needed, and no blocking diode is required due to the internal MOSFET architecture. Thermal feedback regulates the charge current to limit the die temperature during high power operation or high ambient temperature. The charge voltage is fixed at 4.2V, and the charge current can be programmed externally with a single resistor. The BL4054 automatically terminates the charge cycle when the charge current drops to 1/10 the programmed value after the final float voltage is reached. When the input supply (wall adapter or USB supply) is removed, the BL4054 automatically enters a low current state, dropping the battery drain current to less than 2μΑ. The BL4054 can be put into shutdown mode, reducing the supply current to 25μA. Other features include charge current monitor, under-voltage lockout, automatic recharge and a status pin to indicate charge termination and the presence of an input voltage. z z z z z z z z z z z z z Programmable Charge Current Up to 800mA No MOSFET, Sense Resistor or Blocking Diode Required Preset 4.2V Charge Voltage with ±1% Accuracy Charge Current Monitor Output for Gas Gauging Thermal Regulation Maximizes Charge Rate Without Risk of Overheating Charges Single Cell Li-Ion Batteries Directly fro...