Electrode Inductance

In a surface discharge type PDP, the long sustain electrodes are mutually coupled due to unidirectional current flow.  FIG. 1 provides an electrical model for a pair of sustain electrodes E1 and E2 driven by sustainers SA and SB, respectively.  Each electrode has distributed inductances Le, resistances Re and Capacitances Ce and discharge cells 205.

FIG. 1

When sustainer SA rises, current I1 flows into electrode E1, passes through (and charges) capacitances Ce as current I2 and exits electrode E2, flowing into sustainer SB.  Thus, as current flows into SA, it is distributed though the cell capacitances Ce and flows out electrode E2.  The current flow is uni-directional, flowing from left to right when sustainer SA rises.  When sustainer SA falls, the current flows uni-directionally, from right to left.  The each electrode row can be viewed as a single conductor, producing magnetic fields.  When multiple rows are driven, the magnetic fields of adjacent rows are mutually coupled by the uni-directional current flow.  Thus over the entire panel, each pulse produces large magnetic fields alternating in direction according to the uni-directional current flow.

The effect of mutually coupled magnetic fields is an amplification of the inductance of each individual electrode.  While the overall panel inductance may appear low at 10nH, the per electrode inductance for 1080 lines is 10.8uH.