MAX8751

MAX8751 EVALUATION KIT AVAILABLE Fixed-Frequency, Full-Bridge CCFL Inverter Controller General Description The MAX8751 cold-cathode-fluorescent lamp (CCFL) inverter controller is designed to drive multiple CCFLs using the fixed-frequency, full-bridge inverter topology. The MAX8751 operates in resonant mode during striking and switches over to constant-frequency operation after all the lamps are lit. This unique feature ensures reliable striking under all conditions and reduces the transformer stress. The MAX8751 can drive large power MOSFETs typically used in applications where one power stage drives four or more CCFL lamps in parallel. An internal 5.35V linear regulator powers the MOSFET drivers and most of the internal circuitry. The controller operates over a wide input-voltage range (6V to 28V) with high power to light efficiency. The device also includes safety features that effectively protect against many single-point fault conditions, including lamp-out and short-circuit conditions. The MAX8751 achieves a 10:1 dimming range by “chopping” the lamp current on and off using the digital pulsewidth modulation (DPWM) method. The DPWM frequency can be accurately adjusted with a resistor or synchronized to an external signal. The brightness is controlled by an analog voltage on the CNTL pin. The MAX8751 is capable of synchronizing and adjusting the phase of the gate drivers and DPWM oscillator. These features allow multiple MAX8751 ICs to be connected in a daisychain co...