Designing a Rigid-Flex PCB in Standard Rigid-Flex Mode in Altium Designer

Defining the Substacks

The structure of your board is defined in the Layer Stack Manager (Design » Layer Stack Manager). From here, you can enable the required rigid-flex mode and define the substacks needed in your rigid-flex design.

Defining the substacks:

• To enable the features needed to design a rigid-flex board in standard mode, select the Tools » Features » Rigid-Flex command from the main menus of the Layer Stack Manager.
• Add a new substack by clicking the  button at the top of the Layer Stack Manager.
• Check or clear the checkbox for each layer so that only layers required in this substack are enabled.
• Define the properties of the substack (e.g., its Name and if it should be flex) in the Properties panel.

► Learn more about Defining the Substacks - Standard Mode

Defining the Board Shape and Regions

The Board Shape defines the boundary, or extents, of the board in the PCB Editor. The Board Shape is a PCB object (also referred to as the Board Outline) which is essentially a closed polygon. When you create a new PCB document, it is the black area displayed in the PCB editor design space.

There are a number of ways the board shape can be defined. The video below demonstrates using an outline created from lines and arcs on a mechanical layer. Once the overall outline has been defined, it is split into the different rigid and flex regions.

Defining the Board Shape and Regions:

• The board shape can be defined interactively in Board Planning Mode (View » Board Planning Mode), or it can be defined based on an existing outline in 2D layout mode (View » 2D Layout Mode), as demonstrated in the video above.
• To define the board shape from an existing outline, select the outline in 2D layout mode and run the Design » Board Shape » Define Board Shape from Selected Objects command. The software will trace along the centerline of the selected track/arc objects to define the outer edge of the board shape. Note that the ends of the outline tracks/arcs must be coincident for the tracing algorithm to be able to follow the centerline. If it fails, the tracing algorithm will offer to attempt to trace along the outer edge of the selected objects.
• To define the board shape interactively, switch to Board Planning Mode (1 shortcut) and select the Design » Redefine Board Shape command. The standard region object placement behaviors apply during board shape definition, use the Snap Grid and workspace Guides to help with this process. Enable the Board Shape option in the Snap Options palette to give the best level of control during board shape editing. Learn more about Understanding the Snap Behavior.
• To define the Name and assign a Layer stack for each region, double-click on the region. Alternatively, set the PCB panel to Layer Stack Regions mode, where you can examine and edit the regions and bending lines.
• To split a Board Region into two smaller regions, use the Design » Define Split Line command. The command places a straight line between two click locations, when you click within the board shape the first location will be on the board edge closest to where you clicked. Move the cursor to locate the second location, then click a second time. Click and hold on the vertex of a Split Line to move it to a new location.
• The location and shape of an existing Board Region can be edited. Run the Design Design » Edit Board Shape command, then use the standard polygonal object editing techniques to adjust the shape.

► Learn more about Planning Rigid & Flex Regions - Standard Mode

Defining Bends in the Flex Region

Once a flex Region has been created, Bending Lines can be defined in that region. A bending Line is a linear object that is placed across a region.

Defining a Bending Line:

• Bending Lines are placed in Board Planning Mode (1 shortcut).
• To place a Bending Line, run the Design » Define Bending Line command.
• Place the Bending Line across the flexible board Region. It is not necessary to precisely touch each edge of the region with the start and end of the Bending Line, the software will automatically extend it (if too short) or reduce it (if too long). At least one end of the Bending Line must touch or pass over the edge of the Region.
• To edit the properties of a Bending Line, click anywhere within the region to display the vertices for all Bending Lines within that region, then:
  • Double-click on the vertex of a Bending Line to open the Bending Line dialog, or
  • Display the PCB panel and set it to Layer Stack Regions mode, where you can examine and edit the Regions and Bending Lines.
  • Set the Bending Angle and the bend Radius and as required.
  • Bends are folded in the order of their Fold Index, use this feature when the folding order is important to check.
• To move a Bending Line, click and drag on each vertex.
• A Bending Line can be removed by clicking and holding on one of the vertices, then pressing Delete on the keyboard.
• Bending Lines cannot be applied to the edge of a board cutout. If your board requires this, switch to Rigid-Flex Advanced mode.

► Learn more about Defining Bending Lines - Standard Mode