The bq24725 is a high-efficiency, synchronous battery charger, offering low component count for space-constraint, multi-chemistry battery charging applications.The bq24725 uses two charge pumps to separately drive n-channel MOSFETs (ACFET, RBFET and BATFET) for automatic system power source selection.SMBus controlled input current, charge current, and charge voltage DACs allow for high regulation accuracies that can be programmed by the system power management micro-controller.The bq24725 uses internal input current register or external ILIM pin to throttle down PWM modulation to reduce the charge current.The bq24725 charges two, three or four series Li+ cells, and is available in a 20-pin, 3.