Design of resonant backlight inverter by using primary-side control and double-ended driving

A resonant backlight inverter with double-ended driving and primary-side control are proposed to reduce the thermometer effect and leakage current effect in LCD. In this paper, the mathematical model of the lamp current including the parasitical capacitance in LCD panel is conducted to explore the influence of leakage current effect. Moreover, the primary-side control and the DPLL function are integrated to form a feedback mechanism to track the optimal operating frequency. And then the influence of parasitic capacitance can be reduced so as to eliminate the leakage current effect. Experimental results agree with the theoretical predictions.

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