Date: 04/12/2008

I2C USB power manager & Li-Ion charger

The LTC4099 from Linear Technology is an autonomous I2C controlled Li-Ion/Polymer battery charger for 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 I2C. LTC4099 provides a seamless transition between USB and higher voltage power sources.

The other features are,

---Over voltage protection circuit to protect from high USB input voltage
---Power the system even with a dead battery
---Ideal Diode Seamlessly Connects Battery when Input Power is Limited
---The device's ideal diode controller can be used to drive the gate of an optional PFET, reducing the impedance between the load and the battery to 30mOhm or less.
---Charging current up to 600mA from USB port
---Through wall power i.e. AC adapter the charging current of 1.5A is available.
---Protects battery against over-temperature and battery voltage by reducing the chargingvoltage.

---Features also includes, thermal limiting, automatic recharge, stand-alone operation with automatic charge termination and fixed duration safety timer, low voltage trickle charging, bad battery cell detection and a thermistor input for temperature-qualified charging.

An additional feature of the LTC4099 is a suspend LDO that prevents battery drain when a device is connected to a suspended USB port.

Package: 20-pin 3mm x 4mm QFN package
Available: Now
Price: $2.80 each in 1K pieces