The component footprint defines the component mounting and connections on the PCB and can also include 3D
body objects to define the actual component.
The component footprint defines the space and connection points needed to mount the physical component on the printed circuit board. It is a group object made up of a collection of simple primitive objects, which could include pads, lines and arcs, as well as other design objects. The pads provide the mounting and connection points for the component pins. Additional design primitives, such as lines and arcs, are often included to define the outline of the component shape on the component overlay (silkscreen) layer.
The component footprint can also include optional 3D body objects, which define the physical space or envelope of the actual component that is mounted on the board. If the physical component has been defined using 3D body objects or imported STEP models, three-dimensional component clearance checking can be performed.
Component footprints are created in the PCB Library Editor by placing suitable design objects to create the shape required to mount and connect the component. The component reference point is the origin of the Library Editor workspace, which can be set in the Library editor to: pin 1, the geometric center, or a user-defined location on the component.
Locate the component in the Libraries panel (View » Panels » Libraries) then click the Place <ComponentName> button.
PCB component footprints (and schematic components) can only be placed from Available Libraries. The term Available Libraries includes libraries that are part of the current project being worked on, or libraries currently installed in Altium Designer. Libraries can be installed and removed via the Data Management - Installed Libraries page of the Preferences dialog or the Available Libraries dialog (click the Libraries button in the Libraries panel to open it).
PCB component footprints are automatically placed from the available libraries when the design is transferred from the schematic editor to the PCB editor. This is called Design Synchronization, which is a process to detect and resolve the differences between the schematic and the PCB.
The process used to locate the required component footprint will depend on the method chosen to perform placement. Once the required footprint has been chosen for placement and is floating on the cursor:
Press Tab to edit the properties of the component before it is placed.
Press Spacebar to rotate the component anti-clockwise (Shift+Spacebar for clockwise). The default rotation step is 90 degrees, to change this set the Rotation Step value in the PCB Editor - General page of the Preferences dialog.
If the component is being rotated, the Designator and Comment strings can be configured to hold their orientation, or to rotate with the footprint. This behavior is controlled by the Autoposition setting for these strings, the defaults can be set by editing the default Component in the PCB Editor - Defaults page of the Preferences dialog. Note that setting the default will not affect any components that have already been placed.
Press the L shortcut to flip the component to the bottom side of the board. Do not use the X or Y keys as this will mirror the part, but not change its layer.
Placing From the Libraries Panel
To place from the Libraries panel:
The default setting is to only show schematic libraries in the panel, to enable PCB libraries click next to the library selector dropdown and enable Footprints for browsing, as shown below.
Enable PCB libraries for browsing in the Libraries panel.
Once footprint libraries have been enabled, use the dropdown next to the library name to choose the required footprint library for browsing. In the image below the Spirit_Level_Project.PcbLib has been chosen.
The selected component is ready for placing from the Libraries panel.
Use the mask field (below the currently selected library field) to filter the list and speed the searching process, or scroll and select the required part.
Click the Libraries button to open the Available Libraries dialog and add a different library.
Click the Search button to open the Libraries Search dialog and search for a component footprint.
With the part selected in the panel, placement of the component can be made in the following ways:
By clicking the Place button at the top-right of the panel (the button text displays the component that will be placed).
By double-clicking on the selected component.
By clicking and dragging to place the selected component into the workspace. This is a single shot placement technique, meaning only a single instance of the chosen component can be placed. The other methods allow multiple instances to be placed.
The Libraries panel also includes a search feature which can search across available libraries, or all libraries down a folder path. Refer to the Libraries panel page for more information.
Graphical component editing is limited to moving, rotating and flipping. When a component is selected in the workspace it is highlighted in the current selection color, as shown in the image below. To graphically manipulate a selected component:
Press Delete to remove the selected component from the design.
Click and hold to move the selected component, the cursor will jump to the component reference point, or the nearest pad center if the Smart Component Snap option is enabled (PCB Editor - General page of the Preferences dialog).
While a component is moving on the cursor press the Spacebar to rotate it (Shift+Spacebar to rotate in the other direction).
While a component is moving on the cursor press the L key to flip it to the other side of the board.
Click once to select a Component or click and hold to move it.
Press the Spacebar to rotate while moving.
If the component is being rotated, the Designator and Comment strings can be configured to hold their orientation, or to rotate with the footprint. This behavior is controlled by the Autoposition setting for these strings, which can be edited for each component. The default Autoposition behavior can be pre-configured by editing the default Component in the PCB Editor - Defaults page of the Preferences dialog. Autoposition behavior can also be set on-the-fly by pressing Tab while a component is floating on the cursor, note that this will not affect any components that have already been placed.
If attempting to graphically modify an object that has its Locked property enabled, a dialog will appear asking for confirmation to proceed with the edit. If the Protect Locked Objects option is enabled on the Schematic – Graphical Editing page of the Preferences dialog, and the Locked option for that design object is enabled as well, then that object cannot be selected or graphically edited. Click the locked object to select it then disable the Locked property in the List panel or disable the Protect Locked Objects option to graphically edit the object.
The following methods of non-graphical editing are available:
The PCB List panel allows you to display design objects from one or more documents in tabular format, enabling quick inspection and modification of object attributes. Used in conjunction with appropriate filtering - by using the PCB Filter panel, or the Find Similar Objects dialog - it enables the display of just those objects falling under the scope of the active filter – allowing you to target and edit multiple design objects with greater accuracy and efficiency.