Filled polygons and internal planes (how to split a plane)

[Sal Hernandez]

For planes that will be continuous, you can select each layer in the board configuration. From the menu bar select Design then select Board Configuration. Now with a multilayer configuration selected choose which layers you would like to use as planes. Once you have your planes selected press OK. The last step is to assign each plane layer to a net. Do this by hovering your mouse over a trace or ratsnest line with the same net you would like connected to your plane layer. Next, right click and select properties. Near the bottom of the track properties, you will see your inner layers with the words "no nets assigned" next to them. Place a check mark in the box next to the inner layer you would like to assign to the current net. Finally press OK and repeat for all internal plane layers.


If you would like to split the plane layer, you can do so. With the inner layer already assigned to a net, you can divide the layer using a polygon line. Any polygon features added to a plane layer will remove copper. You can assign multiple nets to the same plane layer, but then you must make sure that the nets are separated. In V2, you can select a net name from the Object Hierarchy section of the Project panel the entire net will be highlighted. This will allow you to see the connections on all layers. You can use this to make sure the nets are separated and adjust your polygons accordingly.


You can use the same technique in V3 but the information is in a different location. In V3, select the project tab then PCB Node = PCB Object Hierarchy = PCB board = Children.


An alternative method that will work in both V2 and V3 is to use filled polygons. If you choose to use this method, you should uncheck plane layer selections in the board configuration. As I mentioned earlier, adding polygon features to a plane layer will remove copper. You can add two filled polygons or more to a layer and assign each to a net. Each filled polygon can only be assigned to one net. Once you have the polygon in place, press esc twice to return to the selection tool, then right click on the polygon and select properties. You can change the layer the polygon resides on, name the polygon (optional) and assign the polygon to a net. Now that the polygon has a net assigned, it will only connect to other pins/pad/traces of the same net.


You must make sure that two polygons of different nets are separated. A keep out will not be created if two filled polygons overlap.

Sal