The AAT3693 BatteryManager is a highly integrated single- cell lithium-ion/polymer (Li-Ion) battery charger which operates from a USB port, or an AC adapter input up to 7.5V input voltage. The AAT3693 precisely regulates battery charge voltage and current for 4.2V Li-Ion battery cells. The battery charging current can be set by an external resistor up to 1.6A. Digital Thermal Loop Control maintains the maximum possible battery charging current for the given set of input to output power dissipation and ambient temperature conditions.