19-4562; Rev 1; 12/09
TION KIT EVALUA BLE AVAILA
8-String WLED Driver with Integrated Step-Up Regulator and SMBus/PWM ...
19-4562; Rev 1; 12/09
TION KIT EVALUA BLE AVAILA
8-String WLED Driver with Integrated Step-Up
Regulator and SMBus/PWM Dimming Capability
General Description
The MAX17105 is a high-efficiency driver for white-lightemitting diodes (WLEDs). It is designed for large liquidcrystal displays (LCDs) that employ an array of LEDs as the light source. An internal switch-current mode step-up controller drives the LED array, which can be configured for up to 8 strings in parallel and 10 LEDs per string. Each string is terminated with ballast that achieves Q2% current regulation accuracy, ensuring even LED brightness. The MAX17105 has a wide input voltage range from 6V to 28V, and provides adjustable 0 to 30mA fullscale LED current. The MAX17105 can internally generate a digitally adjusted pulse-width modulation (DPWM) signal for accurate WLED dimming control. The DPWM frequency is resistor programmable, while DPWM duty cycle is controlled directly from an external PWM signal or through a control word through the MAX17105’s SMBus™ interface. This DPWM control provides a dimming range with 8-bit resolution and supports Intel display power-saving technology (DPST) to maximize battery life. The MAX17105 also has direct PWM control mode, in which the PWMI directly controls the LED current turn on/off and the SMBus interface is disabled. The MAX17105 has multiple features to protect the controller from fault conditions. Separate feedback loops limit the output voltage under any circumstance, ...