The most important size limiting parameters of an EL-display are the RC-time constants of the row and column lines, the power consumption arising mainly from the column electrode resistance, and the current capacity of the drivers. In this work the size limits have been analyzed by using circuit simulation methods. With the present standard brightness and resolution, a 1500.1000 20" - 25" display was found to be possible with the non-split structure. Still larger sizes can be manufactured by splitting the columns or rows. A display with both columns and rows split can still be made on a single substrate. With this structure over 40 inch diagonal EL-displays can be made.