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The technical aspects of powering LEDs in backlighting in LCD-TVs and solid state illumination market are presented. A practical solution for direct backlightTVs is discussed. The cost disadvantage of LED versus CCFL in dimmable lamp applications is discussed, and a proposal made to develop a low cost consumer dimmer architecture that enables lowest cost, efficient, dimmable LED lamps to be manufactured.

An adaptive power control scheme is presented for the light-emitting diode (LED) backlighting application. Instead of choosing the worst case output voltage for the DC/DC converter, the adaptive power control scheme adjusts the output voltage to keep track of LED forward voltage variation, reducing the power dissipation of the LED driver system and hence increasing the reliability of the integrated driver solution. Adaptive power control technology and phase shifted PWM dimming have been built into mixed-signal ASICs for TFT-LCD panels. The test bench result shows the power saving of the adaptive power control scheme.