The MAX1811 is a single-cell lithium-ion (Li+) battery charger that can be powered directly from a USB port*or from an external supply up to 6.5V. It has a 0.5% overall battery regulation voltage accuracy to allow maximum utilization of the battery capacity.The charger uses an internal FET to deliver up to 500mA charging current to the battery. The device can be configured for either a 4.1V or 4.2V battery, using the SELV input. The SELI input sets the charge current to either 100mA or 500mA. An open-drain output (CHG) indicates charge status.The MAX1811 has preconditioning that soft-starts a near-dead battery cell before charging. Other safety features include continuous monitoring of voltage and current and initial checking for fault conditions before charging.The MAX1811 is available in a small 1.4W thermally enhanced 8-pin SO package.