A padstack is an entity or pin of a component or a PCB which defines the shape and size of copper that is exposed on PCB board surface. While creating the component footprint, we use padstacks.
Depending upon the layer stackup which we decide, the pads will automatically be assigned in the internal layer.
Each PCB Design Software tool has its own method of creating padstacks, Footprint for the components but the data required is same for all software.
Points to be considered while creation:
- Analyze the datasheet or any other input given for Footprint creation.
- Use the PCB recommended data for footprint creation
- Drill size & pad size are required for padstack creation.
How to create a padstack:
For creating Padstack in SmartDesigner, select the main menu “Design \ PadStack \ Create”.
You will get the padstack creation window, where you can input all the relevant details from the single window. Unit of the padstack while creation is mm. While inserting it to design, takes the priority of the design unit setting.
From SmartDesigner, various padstack types like through hole, mounting hole, SMD and via can be created. They may be with plating or non-plating entities. For a common through hole components, pad shape is normally round but for SMD components its shape varies.
SmartDesigner supports various pad shapes such as round, rectangle, square, oblong and donut. Also it extends to thermal and antipad for the plane layers. Also allows designer to edit the pad information in a specific internal layer using the internal layer edit option present in the dialog.
A thermal relief is a special pattern used where connection are made to an embedded plane that prevents heat from concentrating near a pin or a via. Usually spoked wheel pattern.
SmartDesigner supports positive thermal relief.
Created padstacks will be stored in the master library. This can be inserted in the layout and edited. Padstack manager allows to add them from master library to the local design.