LN2054

LN2054 Standalone Linear Li-Ion Battery Charger with Thermal Regulation ■ General Description The LN2054 is a complete constant-current /constant -voltage linear charger for single cell lithium-ion batteries. Its ThinSOT package and low external component count make the LN2054 ideally suited for portable applications. Furthermore, the LN2054 is specifically designed to work within USB power specifications. 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 LN2054 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 LN2054 automatically enters a low current state, dropping the battery drain current to less than 2µA. The LN2054 can be put into shutdown mode, reducing the supply current to 25µA. Other features include charge current monitor, CHRG GND BAT 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 25...