Component

Parent page: PCB Objects

The component footprint defines the component mounting and connections on the PCB, and can also include 3D
body objects to define the actual component.

Summary

The component footprint defines the space and connection points needed to mount the physical component on the printed circuit board. It is 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. By defining the physical component using 3D body objects or imported STEP models, 3 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.

Availability

Component footprints are created in the PCB Library Editor, and placed in the PCB Editor. To place a component in the PCB editor:

  • Locate the component in the Libraries panel (View | System | ), and click the Place <ComponentName> button.
  • From within an open PCB Library, click Home | Board | , to place the current component into the last active PCB document.
  • 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 that detects and resolves the differences between the schematic and the PCB. Design synchronization is launched from the schematic by clicking Home | Project | Project » Update PCB Document <PcbFileName>.

When using standard libraries (PCBLibs) or integrated libraries (IntLibs), 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, libraries currently installed in the software, or libraries along specified search paths. Libraries can be installed and removed in the Available Libraries dialog (click the Libraries button at the top of the Libraries panel to open it).

Component footprints cannot be placed directly into the PCB Editor from the connected Altium Content Vault. You will need to place a vault component on to a schematic sheet, and then obtain the associated (referenced) PCB component model upon performing a design synchronization.

Placing in the PCB Editor

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:

  1. Press Tab to edit the properties of the component before it is placed.
  2. 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 on the PCB Editor - General page of the Preferences dialog.
  3. If the component is being rotated, the default behavior is for the Designator and Comment strings is to rotate with the footprint. This behavior is controlled by the Autoposition setting for these strings, the default behavior can be set by pressing Tab to edit the settings before the component is placed. Note that setting the default will not affect any components that have already been placed.
  4. 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:

  1. The default setting is to only show schematic libraries in the panel, to enable PCB libraries click the  next to the chosen library field, and enable Footprints for browsing, as shown below.

Enable PCB libraries for browsing in the Libraries panel.

  1. 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 GSM Logger pcb library has been chosen.
  2. 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.

The selected component is ready for placing from the Libraries panel.

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.
The last method 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 first two placement methods will bring up the Place Component dialog.

The Place Component dialog.

Enter a suitable Designator, and include a footprint Comment if required. Click OK, the footprint will appear floating on the cursor, ready for placement. Once placed, the dialog will reappear. Place another instance of the same component, or a different component, or click Cancel to exit placement mode.

The footprint can be changed for a different one, in the same or different PCB library, on-the-fly. To do so:

  1. Click the  button beside the Footprint field in the Place Component dialog to open the Browse Libraries dialog, as shown below.

The Browse Libraries dialog includes a display of the selected footprint, allowing you to visually
select the correct component
.

  1. Select the required library in the Libraries dropdown, and Mask or scroll to locate the required footprint.
  2. Select the component and click OK to return to the Place Component dialog and continue with the placement.

Searching for a Component Footprint

If you cannot locate the required component footprint in the Libraries panel, use the Search feature. To do this, click the Search button to open the Libraries Search dialog (as shown below).

Note that:

  • The default search Scope is to search for Footprints in the Available Libraries (as shown by the Scope options in the image below).
  • Alternatively, the Libraries Search dialog also supports searching through Libraries on a path, stored in folders on a drive. To do this enable the Libraries on Path option, then configure the Path options as required.
  • The Filters are logically AND'ed, it can be better to start with a simpler filter and then if there are many results, use the Refine last search mode to search within the results.
  • Search results are presented in the Libraries panel, clustered under Query Results. If the footprint you choose in the Query Results is from a library that is not currently available, the software will prompt to install the library (note that this feature is not available if you click and drag to place). Re-select a footprint library to return to browsing in the panel.

Search for the footprint in the Available libraries, or search Libraries on a path.

Placing from the Library Editor

A component can also be placed directly from a library that is open in the PCB Library editor. This can be done in two ways:

  • Click Home | Board | , from the main menus.
  • Select the component in the Components region of the PCB Library panel (View | System | ), right-click and choose Place from the context menu.

As with placement from the Libraries panel:

  1. The Place Component dialog will first appear. Specify the designator and any comment as required and click OK.
  2. While the part is floating on the cursor, it can be edited (press Tab), rotated (press Spacebar), or flipped to the other side of the board (press L) before placement.
  3. Once placed, continue placing further instances, or click Cancel in the Place Component dialog to exit placement mode.
If a part is placed directly from a library, that library does not need to be added in the Available Libraries dialog first.

Right-click on the component in the PCB Library editor to place it, or
to update an already-placed component.

Graphical Editing

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 default behavior is for the Designator and Comment strings is 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 set by pressing Tab while a component is floating on the cursor, note that this will not affect any components that have already been placed. To change the text positioning for placed components, use the Tools | Arrange |  » Position Component Text command.

An object that has its Locked property enabled cannot be selected or graphically edited. Double click on the locked object directly and disable the Locked property, to graphically edit the object.

Non-Graphical Editing

The following methods of non-graphical editing are available:

Via an Associated Properties Dialog

Dialog page: Component

This method of editing uses the following dialog to modify the properties of a Component object.

The Component dialog.

The Component dialog can be accessed during placement by pressing the Tab key.

After placement, the dialog can be accessed in one of the following ways:

  • Double-clicking on the placed component object.
  • Placing the cursor over the component object, right-clicking and choosing Properties from the context menu.

Quickly change the units of measurement currently used in the dialog between metric (mm) and imperial (mil) using the Ctrl+Q shortcut. This affects the dialog only and does not change the actual measurement unit employed for the board, as determined by the  and  buttons in the Home | Grids and Units area of the main menus.

Via the PCB Inspector Panel

Panel page: PCB Inspector

The PCB Inspector panel enables the designer to interrogate and edit the properties of one or more design objects in the active document. Used in conjunction with appropriate filtering, the panel can be used to make changes to multiple objects of the same kind, from one convenient location.