General Description
The MAX1574 charge pump drives up to three white LEDs with regulated constant current for uniform intensity. By utilizing adaptive 1x/2x charge-pump modes and very-low-dropout current regulators, it achieves 180mA output drive capability and high efficiency over the 1-cell lithium-battery input voltage range. Fixed-frequency (1MHz) switching allows for tiny external components, and the regulation scheme is optimized to ensure low EMI and low input ripple.

FEATUREs
♦ Up to 180mA (60mA/LED) Drive Capability
♦ 83% Average Efficiency (PLED / PBATT) Over Li+ Battery Discharge
♦ 0.5% (typ) LED Current Matching
♦ Adaptive 1x/2x Mode Switchover
♦ Low Input Ripple and EMI
♦ 5% to 100% Dimming Through Single-Wire Serial Pulse Interface
♦ Low 0.1µA Shutdown Current
♦ 2.7V to 5.5V Supply Voltage Range
♦ Soft-Start Limits Inrush Current
♦ Output Overvoltage Protection
♦ Thermal-Shutdown Protection
♦ 10-Pin 3mm x 3mm TDFN Package

APPLICATIONs
    LCD Backlighting
    Camera Strobes/Flashes and Movie Lights
    Cell Phones/Smart Phones
    PDAs, Digital Cameras, and Camcorders