Voltage-fed push LLC resonant LCD backlighting inverter circuit
An improved electronic LCD backlighting inverter circuit for high frequency operation under low frequency pulse width modulation (PWM) for dimming control. The improved electronic LCD backlighting inverter is based on a voltage-fed push-pull LLC resonant inverter circuit configuration including a resonant inductor (L), magnetizing inductance of an output transformer (L), and resonant capacitor (C). For large values of magnetizing inductance the LLC circuit effectively becomes an LC resonant circuit. By synchronizing the high frequency switching signal and the low frequency modulation frequency using logic control circuitry, a wide dimming range and higher efficiency are achieved under PWM control.
Koninklijke Philips Electronics N.V.
H H
H05B H05B
inventional inventional
Chin
Chang