A liquid crystal display system and CCFL power converter circuit is
provided using a high-efficiency zero-voltage-switching technique that
eliminates switching losses associated with the power MOSFETs. An optimal
sweeping-frequency technique is used in the CCFL ignition by accounting
for the parasitic capacitance in the resonant tank circuit. Additionally,
the circuit is self-learning and is adapted to determine the optimum
operating frequency for the circuit with a given load. An over-voltage
protection circuit can also be provided to ensure that the circuit
components are protected in the case of open-lamp condition.