MAX8901B(2007) Datasheet PDF - Maxim Integrated

General Description
The MAX8901A/MAX8901B step-up converters drive from two to six series-connected white LEDs (WLEDs) with constant current to provide uniform WLED intensity for LCD backlighting in cell phones, PDAs, and other handheld devices. The MAX8901_ operate at a fixed 750kHz (typ) switching frequency, allowing for tiny external components, and are optimized for the highest possible efficiency over the full 1-cell Li+/Li-Poly battery range.

FEATUREs
♦ High Efficiency, Up to 91%
♦ 2.6V to 5.5V Input Voltage Range
♦ Fixed-Frequency Operation
♦ Supplies from 2 to 6 WLEDs with 1% LED Current Accuracy
♦ Flexible Dimming Control
   Direct PWM Dimming (MAX8901A)
   32-Step, 1-Wire Serial Dimming
   (MAX8901B)
♦ Input Undervoltage Lockout
♦ Input Overvoltage Lockout
♦ WLED Overvoltage Protection (25V typ)
♦ 0.01µA (typ) Shutdown Current
♦ No WLED Current in Shutdown
♦ Internal Soft-Start and Thermal Shutdown

APPLICATIONs
   Display Backlight (from 2 to 6 WLEDs)
   Cellular Phones
   PDAs and Smartphones
   MP3 and Portable Media Players
   Portable Navigation Devices
   Digital Cameras