MAX8709B

MAX8709B High-Efficiency CCFL Backlight Controller with SMBus Interface General Description The MAX8709B integrated backlight controller is optimized to drive cold-cathode fluorescent lamps (CCFLs) using a resonant full-bridge inverter architecture. The resonant operation maximizes striking capability and provides near-sinusoidal waveforms over the entire input range to improve CCFL lifetime. The controller operates over a wide input voltage range of 4.6V to 28V with high power-to-light efficiency. The device also includes safetyfeatures that effectively protect against many single-pointfault conditions including lamp-out and short-circuit faults. The MAX8709B achieves 10:1 dimming range by “chop- ping” the lamp current on and off using a digital pulse- width-modulation (DPWM) method. The minimum DPWM duty cycle of the MAX8709B is 12.5%. The brightness is controlled with a 2-wire SMBus-compatible interface. The device directly drives the four external N-channel power MOSF...