Complete the Package Layout

After translation, launch SiP Layout Option to view and modify the package layout as needed.

Allegro layout editors provide manual and automatic tools for placing components, routing, and wire bonding.

Manual and Automatic Placement

With manual placement, you can place elements individually or place elements of the same type during one pass.

In automatic placement, the layout editor places elements based on placement properties you assign that restrict or influence component positioning and part packaging.

In either manual or automatic placement, you can:

• Selectively identify certain parts for placement by attaching a placement “tag” to them.
• Optionally create a floor plan, which is a block diagram of rooms in a design. Rooms are rectangular areas that you create.
  You can use rooms to keep specific logical functions or related elements together in specific areas.

You may want to alternate manual placement with automatic placement. You can preplace sensitive or fixed parts manually, run automatic placement, and then rearrange some autoplaced parts. You could finish by optimizing the overall placement of a design with manual placement.

Placement Tasks

You can use any combination of placement and swap tools. For example, component placement typically involves the following activities:

• Determining design requirements.
• Creating the items required for placement processing (such as grids or package keepin and keepout areas).
• Setting basic placement controls, such as package keepout and keepin areas, placement properties, and automatic placement parameters.
• Running manual placement alternately with automatic placement. You can run different iterations of automatic placement and view the placement results.
• Reviewing placement status and automatic placement results.

Routing Tasks

The PCB layout editor provides tools that help you perform the following when routing physical designs:

• Interactive routing
• Automatic routing with Allegro PCB Router
• Glossing to improve the appearance and manufacturability of a physical design

The following steps describe the basic routing process. The basic routing flow—assuming automatic routing—is the following:

1. Prepare for routing:
   • Check layers to see that layer types and photo film types are correct.
   • Create internal shapes on planes.
   • Create blind and buried vias.
   • Set routing controls (routing areas, constraints and properties, grids, nets, and so on).
2. Manually route critical nets.
3. Define routing parameters in Allegro PCB Router to control how automatic routing functions.
4. Run Allegro PCB Router.
5. Review routing results.
6. Interactively finish or correct etch.
7. Gloss the design.
8. Optionally analyze the design for signal integrity or EMI.

Related Topic

Placing the Elements

Routing the Design

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