The ADP3500 is a multifunction power system chip optimized for CDMA cell phone power management. It contains 15 LDOs. Sophisticated controls are available for power up during battery charging, keypad interface, GPIO/INT function and RTC function. The battery charger has four modes as Pre-charge, Low Current Charge, Full Current Charge, and Regulator modes, and is designed for Li-Ion/Li-Polymer batteries.