AF4057

AF4057 1.1A Lithium Ion Battery Linear Charger GENERAL DESCRIPTION AF4057 is a complete CC/CV linear charger for single cell lithium-ion batteries. It is specifically designed to work within USB power Specifications. No external sense resistor is needed and no blocking diode is required due to the internal P-MOSFET architecture. Thermal feedback regulates the charge current to limit the die temperature during high power operation or high ambient temperature .The charge voltage is fixed at 4.35V, and the charge current can be programmed externally with a single resistor. The AF4057 automatically terminates the charge cycle when the charge current drops to 1/10th the programmed value after the final float voltage is reached. When the input supply (wall adapter or USB supply) is removed the AF4057 automatically enters a low current state dropping the battery drain current to less than 2μA.The AF4057 can be put into shutdown mode reducing the supply current to 55μA. Other features includ...