MAX1570(2002) Datasheet PDF - Maxim Integrated

General Description
The MAX1570 fractional charge pump drives up to five white LEDs with regulated constant current for uniform intensity. The MAX1570 maintains the highest possible efficiency over the full 1-cell lithium-ion (Li+) battery input voltage range by utilizing a 1x/1.5x fractional charge pump and very-low-dropout current regulators.

FEATUREs
♦ Excellent 0.3% LED-to-LED Current Matching
♦ 30mA/LED Drive Capability
♦ Proprietary 1x/1.5x Modes for Ultra-High
   Efficiency
♦ Low Input Ripple and EMI
♦ Eliminates Ballast Resistors
♦ Digital or PWM LED Dimming Control
♦ 0.1µA Shutdown Current
♦ 2.7V to 5.5V Supply Voltage Range
♦ Soft-Start Limits Inrush Current
♦ Thermal-Shutdown Protection
♦ No External Inductor, Schottky, or Zener Diode
   Required
♦ Tiny 16-Pin 4mm ✕ 4mm Thin QFN Package

APPLICATIONs
   White LED Backlighting
   Cell Phones and Smart Phones
   PDA and Palmtop Computers
   Portable MP3 Players
   Digital Cameras and Camcorders