WS4518E

WS4518E 300mA, Single Li-ion Battery Charger WS4518E www.sh-willsemi.com Descriptions The WS4518E 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 WS4518E automatically terminates the charge cycle when the charge current drops to 3/10 the programmed value after the final float voltage is reached. When the input supply (wall adapter or USB supply) is removed, the WS4518E automatically enters a low current state, dropping the battery drain current to less than 0.5uA. The WS4518E can be put into shutdown mode, reducing supply current to 40uA (Typ.). The WS4518E is available in...