The ISL9203A is an integrated single-cell Li-ion or Li-polymer battery charger capable of operating with an input voltage as low as 2.4V. This charger is designed to work with various types of AC adapters. The ISL9203A operates as a linear charger when the AC adapter is a voltage source. The battery is charged in a CC/CV (constant current/constant voltage) profile. The charge current is programmable with an external resistor up to 1.5A. The ISL9203A can also work with a current-limited adapter to minimize the thermal dissipation, in which case the ISL9203A combines the benefits of both a linear charger and a pulse charger. The ISL9203A features charge current thermal foldback to guarantee safe operation when the printed circuit board is space limited for thermal dissipation. Additional features include preconditioning of an over-discharged battery and thermally enhanced DFN package.