DESCRIPTION
The LTC®3559/LTC3559-1 are USB battery chargers with dual high efficiency buck regulators. The parts are ideally suited to power single-cell Li-Ion/Polymer based handheld applications needing multiple supply rails.

FEATURES
Battery Charger
■ Standalone USB Charger
■ Up to 950mA Charge Current Programmable via Single Resistor
■ HPWR Input Selects 20% or 100% of Programmed Charge Current
■ NTC Input for Temperature Qualified Charging
■ Internal Timer Termination
■ Bad Battery Detection
■ CHRG Indicates C/10 or Timeout

Buck Regulators
■ 400mA Output Current
■ 2.25MHz Constant Frequency Operation
■ Zero Current in Shutdown
■ Low Noise Pulse Skip Operation or Power Saving Burst Mode Operation
■ Low No-Load Quiescent Current: 35μA
■ Available in a Low Profi le Thermally Enhanced 16-Lead 3mm × 3mm QFN Package

APPLICATIONS
■ SD/Flash-Based MP3 Players
■ Low Power Handheld Applications