Power manager Li-ion charger provides digital control, status info

Power manager Li-ion charger provides digital control, status info

Float voltage, limit, termination, and charge current are programmable via I2 C

An autonomous I2 C-controlled power manager, ideal diode controller, and Li-ion/polymer battery charger, the LTC4099 targets portable USB-powered devices such as media players, digital cameras, PDAs, PNDs and smart phones. Parameters including input current limit, charge current, termination current, and float voltage can be programmed via I2 C. The I2 C port also allows the user to read back system status information. It manages power flow between a wall adapter or USB port and the device’s battery while preferentially providing power to the system load.

The power manager device uses an OVP circuit to prevent damage caused by accidental application of high voltage on the USB input. An onboard ideal-diode guarantees ample power is available to VOUT , even if there is insufficient power at the two input pins.

The single-cell Li-ion/polymer battery charger allows the load current to exceed the current drawn from the USB port while conforming to USB load specifications. For fast charging, the IC’s switching input stage converts nearly all the 2.5 W available from the USB port to current, enabling up to 600-mA charge current or 700-mA system load current from a 500-mA-limited USB port. When the device is wall powered, 1.5-A charge current is also available. (From $2.80 ea/1,000 available now.)

Linear Technology , Milpitas , CA
Information 408-432-1900
http://www.linear.com