The MAX8662/MAX8663 power-management ICs (PMICs) are efficient, compact devices suitable for smart cellular phones, PDAs, Internet appliances, and other portable devices. They integrate two synchronous buck regulators, a boost regulator driving two to seven white LEDs, four low-dropout linear regulators (LDOs), and a linear charger for a single-cell Li-ion (Li+) battery. Maxim’s Smart Power Selector (SPS) safely distributes power between an external power source (AC adapter, auto adapter, or USB source), battery, and the system load. When system load peaks exceed the external source capability, the battery supplies supplemental current. When system load requirements are small, residual power from the external power source charges the battery. A thermal-limiting circuit limits battery-charge rate and external power-source current to prevent overheating. The PMIC also allows the system to operate with no battery or a discharged battery. ..