AN2503

PDP basic

7/30

When the polarity of the sustain pulse is reversed, the potential difference across the gap

becomes larger than Vbd by an amount determined by the wall charges, and a new large

discharge of different polarity occurs, as shown in Figure 6.

Figure 6.

Memory effect - discharge

Figure 7.

Memory effect - wall charges deposit

The next discharge starts as the polarity of the sustain pulse is reversed, as shown in

Figure 8.

Figure 8.

Memory effect - discharge with reverse polarity

Once the discharge is initiated, it continues as long as the sustain pulse is applied. Due to

this memory characteristic of AC PDPs, lower sustain voltage (< Vbd) pulses can maintain

the ac PDPs to light.

In other words, the process of panel image displaying depends on a former process of panel

addressing. In fact, during the address phase a small amount of charges (wall charges)

deposit on the selected electrodes without any visible light emission. This reduces the

Address = Vs/2

X = GND

Y = Vs

3

Address = Vs/2

X = GND

Y = Vs

Address = Vs/2

X = Vs

Y = GND