The Drill-Pair Manager dialog provides controls to configure the required drill pairs for the active layer stack. Drill pairs must be configured when blind, buried, or build-up type vias are to be used, with a drill pair for each layer-pair that a via spans. It is the presence of drill pairs that lets the system know that blind and/or buried vias are in use. This ensures that when the fabrication output files are generated from the completed board, there are suitable drill files for the various drill jobs that must be performed to create the blind and/or buried vias.
Once the drill pairs have been defined, suitable blind, buried or thru-hole vias are automatically placed during routing in accordance with the drill pair settings and the applicable Routing Via Style design rule.
The dialog is accessed from the PCB Editor in one of the following ways:
Layer Stack - this read-only field displays the active stack for which the drill pairs are being configured. The active stack is changed by clicking on the required stack graphic in the Layout region of the Layer Stack Manager dialog. A board always has a default Board Layer Stack, which reflects the overall stackup for that board. In addition, additional user-defined stacks can be added and defined. These are typically used in Rigid-Flex designs, where different regions of the board require different layer stack-ups.
Drill Pairs - this region of the dialog lists all currently defined drill pairs. Each drill pairing consists of a Start Layer and a Stop Layer. There always will be at least one drill pair defined for the default Board Layer Stack, pairing the Top Layer with the Bottom Layer.
Add - click this button to manually add a new drill pair to the list. The Drill-Pair Properties dialog opens in which you can determine the start and stop layers for the pairing.
Delete - click this button to delete the currently selected drill pair. A confirmation dialog will appear Click Yes to effect the removal.
The Top Layer - Bottom Layer drill pair cannot be deleted from the default Board Layer Stack.
Drill Pair Properties - click this button to edit the currently selected drill pair. The Drill-Pair Properties dialog will open in which you can modify the start and stop layers for the pairing.
The Top Layer - Bottom Layer drill pair that is defined for the default Board Layer Stack cannot be edited.
Create Pairs From Layer Stack - click this button to remove the current drill pairs, and replace them with pairs created from the current layer stack. A confirmation dialog will appear. Click Yes to effect the replacement.
Create Pairs From Used Vias - click this button to remove the current drill pairs and replace them with pairs created based on the actual vias currently used within the region of the design associated with the active layer stack. A confirmation dialog will appear. Click Yes to effect the replacement.
Menu - click this button to access a list of commands providing the same functionality as the buttons available in the dialog.
These same commands are also available on the right-click menu, accessed by right-clicking in the Drill Pairs list region.
Drill pairs must be defined to suit the layer stack-up style. This should be done in consultation with your board manufacturer to ensure that your design matches their fabrication technology.