The STw4102 allows dual charging capability using the main input adaptor up to 1A (Wall adaptor, Car adaptor) or USB cable up to 500mA without external component. Upper 1A charging is possible by adding just one external transistor. The STw4102 offers programmable fast charge current up to 1A with external resistor. A thermal regulation circuitry limits the charge current against the die high power dissipation or high ambient temperature. An end of charge output pin indicates the charge termination when the fast charge current drops below 10% of the programmed current value.