DESCRIPTION
The LTC®3550-1 is a standalone linear charger with a 600mA monolithic synchronous buck converter. It is capable of charging a single-cell Li-Ion battery from both wall adapter and USB inputs. The charger automatically selects the appropriate power source for charging.

FEATURES
■ Charges Single-Cell Li-Ion Batteries from Wall
   Adapter and USB Inputs
■ Automatic Input Power Detection and Selection
■ Charge Current Programmable Up to 950mA from
   Wall Adapter Input
■ High Effi ciency 600mA Synchronous DC/DC
   Converter
■ No External MOSFET, Sense Resistor or Blocking
   Diode Needed
■ Thermal Regulation Maximizes Charge Rate Without
   Risk of Overheating*
■ Preset Charge Voltage with ±0.6% Accuracy
■ Programmable Charge Current Termination
■ 1.5MHz Constant Frequency Operation (Step-Down
   Converter)
■ 18μA USB Suspend Current in Shutdown
■ Independent “Power Present” Status Outputs
■ Charge Status Output
■ Automatic Recharge
■ Available in a Thermally Enhanced, Low Profi le
   (0.75mm) 16-Lead (5mm x 3mm) DFN Package

APPLICATIONS
■ Cellular Telephones