LTC4089-3

The LTC4089-3 is a USB power manager plus high voltage Li-Ion battery charger. This device controls the total current used by the USB peripheral for operation and battery charging. Battery charge current is automatically reduced such that the sum of the load current and the charge current does not exceed the programmed input current limit. The LTC4089-3 also accommodates high voltage power supplies, such as 12V AC/DC wall adapters, Firewire, or automotive power.

The LTC4089-3 provides an adaptive output that tracks the battery voltage for high efficiency charging from the high voltage input. This 3.95V version of the the standard LTC4089 is intended for applications which have extended battery lifetime requirements or those that require high temperature (approximately >60°C) operation or storage. Under these conditions, a reduced float voltage will trade-off initial cell capacity for the benefit of increased capacity retention over the life of the battery. The charge current is programmable and an end-of-charge status output (CHRG) indicates full charge. Also featured are programmable total charge time, an NTC thermistor input used to monitor battery temperature while charging and automatic recharging of the battery.

Applications

• Portable USB Devices—GPS Receivers, Cameras,MP3 Players, PDAs