LTC4089-3

LTC4089-3 USB Power Manager with High Voltage Switching Charger Features nn Seamless Transition Between Power Sources: Li-Ion Battery, USB, and 6V to 36V External Supply nn High Efficiency 1.2A Charger from 6V to 36V Input with Adaptive Output Control nn 3.95V Float Voltage Improves Battery Lifespan and High Temperature Safety Margin nn Load Dependent Charging from USB Input Guarantees Current Compliance nn 215m Internal Ideal Diode plus Optional External Ideal Diode Controller Provides Low Loss Power Path When External Supply/USB Not Present nn Constant-Current/Constant-Voltage Operation with Thermal Feedback to Maximize Charging Rate without Risk of Overheating nn Selectable 100% or 20% Current Limit (e.g., 500mA/100mA) from USB Input nn Preset 3.95V Charge Voltage with ±0.8% Accuracy nn C/10 Charge Current Detection Output nn NTC Thermistor Input for Temperature Qualified Charging nn Tiny (6mm × 3mm × 0.75mm) 22-Lead DFN Package Applications nn Portable USB Devices—GPS Receivers, Cameras, MP3 Players, PDAs Description The LTC®4089-3 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...