The EUP8207 is a constant current, constant voltageLi-Ion battery charger controller that uses a current modePWM step-down (buck) switching architecture. With a500kHz switching frequency, the EUP8207 provides asmall, simple and efficient solution to fast charge one(4.2V) or two (8.4V) cell lithium-ion batteries.The EUP8207 charges the battery in three phases:conditioning, constant current, and constant voltage. Anexternal sense resistor sets the charge current with ±10%accuracy. An inte