The bq24133 device is a highly integrated stand-alone Li-Ion and Li-Polymer switched-mode battery charger with two integrated N-channel power MOSFETs. The device offers a constant-frequency synchronous PWM controller with high accuracy regulation of input current, charge current, and voltage. The bq24133 closely monitors the battery pack temperature to allow charge only in a preset temperature window. The bq24133 charges one, two, or three cells (selected by CELL pin) at a fixed 4.2 V/cell.