The LTC4099 is an I2C controlled high efficiency USB PowerPath™controller and full-featured Li-Ion/Polymer battery charger. It seamlessly manages power distribution from multiple sources including USB, a wall adapter and a Li-Ion/Polymer battery.The LTC4099 automatically limits its input current for USB compatibility. For automotive and other high voltage applications, the LTC4099 interfaces with an external switching regulator. Both the USB input and the auxiliary input controller feature Bat-Track optimized charging to provide maximum power to the application and reduced heat in high power density applications.The I2C port allows digital control of important application parameters including input current limit, charge current and float voltage. Several status bits can also be read back via I2C.An overvoltage protection circuit guards the LTC4099from high voltage damage on the low voltage VBUSpin.TheLTC4099 is available in a 20-Lead 3mm × 4mm × 0.75mmQFN Package.ApplicationsMedia PlayersPortable Navigation DevicesSmart PhonesIndustrial HandheldsPortable Medical Instruments