APPLICATIONS
GENERAL DESCRIPTION
When charging from wall adapter, the PT1505 increases the charging current automatically. The battery charger is a highly integrated charging management device targeted at space limited portable applications. It offers an integrated MOSFET and current sensor, reverse blocking protection, high accuracy current and voltage regulation, and charge termination. It charges a battery in three phases: trickle charging, constant current and constant voltage. No external sense resistor is needed, and no blocking diode is required due to the internal MOSFET architecture. The thermal feedback regulates the charging current to limit the chip temperature during high power operation or high ambient temperature to maximize the charge rate without risk of overheating. The charge voltage is fixed at 4.2V, and the charge current can be programmed externally with a single resistor. The PT1502 automatically terminates the charge cycle when the charge current drops to 1/10 the programmed value after the final float voltage is reached.