General Description
The MAX8831 integrates a 60mA, 28V PWM DC-DC step-up converter with five low-dropout LED current regulators for display and keypad backlighting in cell phones, PDAs, and other portable devices. The IC provides up to 90% efficiency over the entire input voltage range of 2.7V to 5.5V. The step-up converter operates at a fixed 2MHz switching frequency, enabling the use of very small external components to achieve a compact circuit area. For improved efficiency, the step-up converter automatically transitions to pulse-skipping mode at light loads.

FEATUREs
♦ 28V Step-Up DC-DC Converter
   Integrated NMOS Power Switch
   > 90% Efficiency
   Fixed 2MHz Switching
   Pulse Skipping for Improved Light-Load Efficiency
   Tiny External Components
♦ I2C Programmable (0x9A Write/0x9B Read), Compatible with 1.8V Logic
♦ Two 25mA Regulators for Display Backlighting
   I2C-Programmable Output Current (50µA to 25.25mA)
   128-Step Logarithmic Dimming
   Individually Programmable Ramp (Up/Down) Timers
   Low Dropout (200mV max)
♦ Three 5mA Current Regulators for Keypad Lighting
   I2C-Programmable Output Current (50µA to 5.0mA)
   32-Step Logarithmic Dimming
   Individually Programmable Ramp (Up/Down) Timers
   Individual Blink Rate and Duty Cycle Timers
   Low Dropout (150mV max)
♦ Open/Short LED and Open-Circuit Diode Detection
♦ Thermal-Shutdown and Output Overvoltage Protection
♦ Ultra-Low 0.1mA Shutdown Current
♦ Tiny 2mm x 2mm, 16-Bump WLP Package

APPLICATIONs
   Cell Phones
   PDAs
   Smartphones