Abstract
Knowing how a component is mounted is information we use to plan and calculate the assembly, so it is required to include the mount type in your production files.
Mount types
We categorize components into SMD or THT parts.
SMD/ Surface Mount Components are placed on one side of the PCB, they can be populated using a pick and place machine and reflow soldered, this makes them very economical.
THT or Through Hole Technology describes components whose pins/leads are inserted into the PCB and soldered to contact on the other side. They are more sturdy and thus better suited for mechanically demanding applications, but they cannot be placed with a pick and place machine and require special solder processes like wave or selective soldering.
Some components like USB-C connector have both surface mount pads and trough hole retention pins, as it is possible to reflow solder these components they can be categorized as SMD part.
We can summarize: A component is categorized as SMD when it mounts to one side of the PCB and can be reflow soldered. Parts with leads through the PCB that cannot be soldered using reflow are categorized as THT parts.
You can contact our support if you are unsure which option you should choose for your component.
New footprint
When creating a new footprint in KiCad you will be promoted to select the mount type, select it according to our guidance above.
Update an existing footprint
An existing footprint with a mismatching mount type can be easily updated.
Setting the mount type in the footprint editor is the preferred method, it ensures that the changes will be applied to all future PCBs.
1. Head to the Footprint Editor:
2. Select the footprint using the tree view
3. Edit the footprint properties.
4. Update the mount type.
Select it using the guidance provided by us. Save the footprint with Ctrl + S.
5. Apply changed to the PCB
We now need to apply our changes to the PCB, open the PCB editor, right-click on the footprint that you want to update. Select Update Footprint.
This will open up a new dialog, select if you would like to update all the footprints in your layout or just the one you selected. Review the changes and save the PCB file using Ctrl + S .
6. Upload the new revision.
Head to the project overview, there you will find an option to upload a new revision.
During an ongoing order, you have to contact our support staff to update the revision for you.
Update a footprint when only the PCB file is available
KiCad also allows updating the mount type in the PCB editor alone, this change will solely apply to that particular footprint, use it only when you have lost the original KiCad project or library.
1. Update the footprint mount type.
Open the PCB editor, right-click on the footprint that you want to update. Select ``Properties.
Set the mount type in the Fabrication Attributes section of the property panel.
Save the PCB board file using Ctrl + S .
2. Upload a new revision.
Head to the project overview, there you will find an option to upload a new revision.
During an ongoing order, you have to contact our support staff to update the revision for you.