Sustain Driving Method With High-Impedance State for Plasma Display Panel

A new sustain driving method with a high-impedance state for alternating current plasma display panels (ac PDP) is proposed. In this method, the voltage applied to scan and common electrodes of the ac PDP has three states during one sustain cycle, namely, positive-voltage, high-impedance, and negative-voltage states. The positive- and negative-voltage states occur alternately. The high-impedance state occurs between the positive- and negative-voltage states. During the positive and negative states, the glow discharge forms in the on-state cells, and the wall charges are accumulated on the dielectric layer. The high-impedance state is used to interrupt the current flow during the polarity change of the applied voltage and can suppress the loss of wall charges between adjacent gas discharges, thus improving the stability of the sustain discharge in the ac PDP. The experimental results on a 12-in PDP test panel show that the wall charges increase by 15% during the sustain period, the dynamic sustain voltage margin increases by 100%, and the brightness increases by 5%.