General Description

The MAX1577Y/MAX1577Z charge pumps drive white LEDs, including camera strobes, with regulated current up to 1.2A (guaranteed to 800mA). The very low openloop output resistance allows high flash brightness, even from a low battery input voltage. The adaptive 1x/2x regulating charge-pump operation provides high efficiency (up to 92) while in movie mode or backlighting. Fast (1MHz) switching allows the use of tiny external components.

Features

♦ Up to 1.2A Output Drive Capability (800mA

   Guaranteed)

♦ Up to 92 PLED / PBATT Efficiency for Movie

   Mode

♦ Flexible Brightness Control

   Two-Bit Logic for 100, 33, 20, and Off

   PWM for 20 to 100

♦ 3 Current Regulation Over Line and

   Temperature

♦ Current or Voltage Regulation for Flash and

   Backlighting (MAX1577Y)

♦ Current Regulation for Flash (MAX1577Z)

♦ Low Ripple and EMI

♦ 2.7V to 5.5V Supply Voltage Range

♦ Soft-Start Limits Inrush Current

♦ Output-Voltage Regulation Mode

♦ Thermal-Shutdown Protection

♦ 8-Pin 3mm x 3mm TDFN Package

Applications

   White LED Flashes, Strobes, and Movie Lights

   LCD Backlighting

   Camera Phones, Cell Phones, and Smart Phones

   PDAs, Digital Cameras, and Camcorders