ISL6299A

® ISL6299A Data Sheet January 3, 2006 FN9212.1 Li-ion/Li-Polymer Battery Charger Accepting Two Power Sources The ISL6299A is a fully integrated low-cost single-cell Li-ion or Li-polymer battery charger. The charger accepts two power inputs, normally one from a USB (Universal Serial Bus) port and the other from a desktop cradle. The ISL6299A is an ideal charger for smart handheld devices that need to communicate with a personal computer via USB. The ISL6299A features 28V and 7V maximum voltages for the cradle and the USB inputs respectively. Due to the 28V rating for the cradle input, low-cost, large output tolerance adapters can be used safely. When both inputs are powered, the cradle input is used to charge the battery. The charge current is programmable for the cradle input with a small resistor. The end-of-charge current for the cradle input is also programmable by another external resistor. The charger incorporates Thermaguard™ which protects the IC against over temperature. If the die temperature rises above a typical value of 100°C, a thermal foldback function reduces the charge current automatically to prevent further temperature rise. The charger preconditions the battery with low current when the battery voltage is below 2.6V. The charger has two indication pins. The PPR (power present) pin outputs an open-drain logic LOW when either the cradle or the USB input power is attached. The CHG (charge) pin is also an open-drain output that indicates a logic LOW when the ...