General Description
The MAX8790A is a high-efficiency driver for white light emitting diodes (LEDs). It is designed for large liquid crystal displays (LCDs) that employ an array of LEDs as the light source. A current-mode step-up controller drives up to six parallel strings of multiple series-connected LEDs. Each string is terminated with ballast that achieves ±1.5% current regulation accuracy, ensuring even brightness for all LEDs. The MAX8790A has a wide input-voltage range from 4.5V to 26V, and provides a fixed 20mA or adjustable 15mA to 27mA full-scale LED current.

Features
● Drives Six Parallel Strings with Multiple SeriesConnected LEDs per String
● ±1.5% Current Regulation Accuracy Between Strings
● Low 450mV Feedback Voltage at Full Current Improves Efficiency
● Step-Up Controller Regulates the Output Just Above the Highest LED String Voltage
● Full-Scale LED Current Adjustable from 15mA to 27mA, or Preset 20mA
● Wide 100:1 Dimming Range
● Programmable Dimming Control: Direct DPWM or Analog Dimming
● Built-In PLL for Synchronized Dimming Control
● Open and Short LED Protections
● Output Overvoltage Protection
● Wide Input Voltage Range from 4.5V to 26V
● External MOSFET Allows a Large Number of LEDs per String
● 500kHz/750kHz/1MHz Switching Frequency
● Small, 20-Pin, 4mm x 4mm Thin QFN Package

Applications
● Notebook, Subnotebook, and Tablet Computer Displays
● Handy Terminals