DESCRIPTION
The LTC®4090/LTC4090-5 are USB power managers plus high voltage Li-Ion/Polymer battery chargers. The devices control 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 LTC4090/LTC4090-5 also accommodate high voltage power supplies, such as 12V AC/DC wall adapters, Firewire, or automotive power.

FEATURES
■ Seamless Transition Between Power Sources:
   Li-Ion Battery, USB, and 6V to 36V Supply (60V Max)
■ 2A Output High Voltage Buck Regulator with
   Bat-Track™ Adaptive Output Control (LTC4090)
■ Internal 215mW Ideal Diode Plus Optional
   External Ideal Diode Controller Provides Low Loss
   PowerPath™ When External Supply/USB Not Present
■ Load Dependent Charging from USB Input
   Guarantees Current Compliance
■ Full Featured Li-Ion Battery Charger
■ 1.5A Maximum Charge Current with Thermal Limiting
■ NTC Thermistor Input for Temperature Qualified
   Charging
■ Tiny (3mm × 6mm × 0.75mm) 22-Pin DFN Package

APPLICATIONS
■ HDD-Based Media Players
■ Personal Navigation Devices
■ Other USB-Based Handheld Products
■ Automotive Accessories