We’re almost to the point where you can start arranging components in your PCB layout. However, before you do this, there is an important task we need to complete: designing the PCB layer stack. You might have noticed that, in the previous lessons, we’ve made a big deal about stackup design. The arrangement of signal and plane layers in your PCB stackup will determine how electrical signals travel in your board, as well as the stability of DC power in your board, so it’s important to make sure this step is completed before you place components and start routing.
ECAD software applications will include a tool that allows you to set your power, ground, and signal layers in your PCB stackup. You’ll have the option to designate certain layers as planes or signals, and you can select materials for your PCB stackup.
Functions of Different Layers
To get started designing your layer stack, you’ll use the Layer Stack Manager in Altium Designer. You can access this tool by first opening your PCB file, and then select the Design → Layer Stack Manager option from the top menu. Once you’re inside the Layer Stack Manager, there are several commands you can use to configure the layers in your board. Some of the tasks you’ll need to complete include:
- Set plane and signal layers
- Specify core and prepreg layers
- Define via transitions
- Calculate impedance
- Specify materials constants
- Select copper weight on each layer
The following video shows how to perform these tasks in the Layer Stack Manager in Altium Designer.