Image Number 4 for United States Patent #6628275.
A full-bridge driver circuit comprising four controllable switches supplies a voltage having alternating polarities between a first and a second electrode of a flat panel display. A series arrangement of a capacitance present between the first and a second electrode, an inductor, and a diode, is arranged in parallel with one of the switches. The diode is poled to be conductive during a resonance phase. The control circuit closes one of the switches so that the inductor and the capacitance form a resonant circuit to reverse the polarity of the voltage in an energy-efficient way without requiring any other controllable switches than the ones forming the full-bridge driver circuit.