Altium NEXUS Documentation

Situs Strategy Editor

Modified by Susan Riege on Apr 21, 2018


The Situs Strategy Editor dialog

Summary

This dialog allows you to fully define a routing strategy for the Situs Autorouter, including its constituent routing passes (algorithms). The inclusion of various routing passes and the order in which they are used constitutes the Autorouter's 'intelligence'. These passes are used to turn the virtual routing paths identified in the topological map, into high-quality routes on the board.

Access

The dialog is accessed from the PCB Editor through the Situs Routing Strategies dialog (Route » Auto Route » Setup or Route » Auto Route » All from the main menus) in one of the following ways:

  • Click the Add button.
  • Select an existing, user-defined routing strategy then click the Edit button.
Options/Controls

Options

  • Strategy Name - the current name for the strategy. If creating a new routing strategy, this field will contain the default entry New Strategy. Edit this field to give a more meaningful name as required.
  • Strategy Description - the current description for the strategy. Enter a meaningful description that summarizes the purpose or scope of the strategy.
  • More/Less Vias - use this slider bar to define permitted via usage by the Autorouter. This is a trade-off between greater routing speed and the use of fewer vias. Moving the bar to the right will constrain the Autorouter to place less vias, however, the time taken to route the board will be greater. Moving the bar to the left achieves faster routing completion times, however, at the expense of extra vias placed by the Autorouter on the PCB.
  • Orthogonal - enable this option to constrain the Autorouter to routing orthogonal (90°) paths only. Disabling this option allows the Autorouter to route orthogonally or non-orthogonally (45°) as it sees fit.

Routing Passes

  • Available Routing Passes - this area lists the available routing passes (algorithms) that can be used in a routing strategy. The following passes are available:
    • Adjacent Memory - this is a connection-level routing pass. It is used to route adjacent same-net pins requiring fan-out with a simple U pattern.
    • Clean Pad Entries - this is a connection-level routing pass. It reroutes out from each pad center along the longest axis of the pad.
For designs that include components with pads that have different X and Y dimensions, always include a Clean Pad Entries pass after the Memory pass.
  • Completion - this is a connection-level routing pass. It is essentially the same as the Main pass, costed differently to resolve conflicts and complete difficult connections. Examples of costing differences include vias being cheaper and wrong-way routes being dearer.
  • Fan out Signal - this is a component-level pass, based on the fanout settings defined by the Fanout Control. It checks for patterns in pads, considers clearance, routing width and via style, then selects a suitable fan out arrangement (inline row, staggered, etc.) to meet the requirements defined in the design rule. Fanout is to signal layers only.
  • Fan out to Plane - this is a component-level pass, based on the fanout settings defined by the Fanout Control. It checks for patterns in pads, considers clearance, routing width and via style, then selects a suitable fan out arrangement (inline row, staggered, etc.) to meet the requirements defined in the design rule. Fanout is to an internal plane layer only.
  • Globally Optimised Main - this is a connection-level routing pass. It provides optimal routing. It ignores contentions/violations on its first iteration. It then reroutes connections, with increased conflict costs, until there are no violations remaining. This pass, used in conjunction with the Orthogonal option enabled, can produce nicely routed patterns. Add a Recorner pass to the strategy to provide mitered cornering.
  • Hug - this is a connection-level routing pass that reroutes each connection, following existing routing with the minimum clearance possible. The hug pass is used to maximize free routing space. Note that this pass is very slow.
  • Layer Patterns - this is a connection-level routing pass. It only routes connections that match a layer direction (within a tolerance). It is costed to hug or follow existing routing to maximize free space.
  • Main - this is a connection-level routing pass. It uses the topological map to find a routing path, then uses the push and shove router to convert the proposed path to actual routing.
  • Memory - this is a connection-level routing pass. It checks for two pins on different components on the same layer that share X or Y coordinates.
  • Multilayer Main - this is a connection-level routing pass. It is similar to the Main pass, but with costs optimized for multi-layer boards.
  • Recorner - this is a connection-level routing pass that is used to provide mitering of routed corners. This pass is used when the Orthogonal option is enabled for the strategy - essentially overriding it and mitering the corners of each route. If the Orthogonal option is disabled for the strategy being used, there is no need to include a Recorner pass as the autorouter will miter corners by default.
  • Spread - this is a connection-level routing pass that reroutes each connection, attempting to spread the routing to use free space and equally space routing when it passes between fixed objects (such as component pads). Note that this pass is very slow.
  • Straighten - this is a connection-level routing pass that attempts to reduce the number of corners. It does this by walking along the route to a corner, then from that corner performs a (horizontal/vertical/45up/45down) probe searching for another routed point on the net. If one is found, it then checks to see if this new path reduces the routed length.
Only one main-type pass should be specified for a routing strategy - either Main, Multilayer Main, or Globally Optimized Main.
  • Passes in this Routing Strategy - this area lists the actual routing passes (algorithms) included in the strategy. You can add whatever passes you wish from the list of available passes and multiple instances of the same pass may be added throughout the overall strategy to achieve specific results. Passes will be executed, in order, from the top down. This order can be modified using the Move Up and Move Down buttons.
  • Add - click this button to add the currently selected pass in the Available Routing Passes list to the Passes in this Routing Strategy list. The pass will be added above the currently selected pass in the latter.
  • Remove - click this button to remove the currently selected pass in the Passes in this Routing Strategy list from the strategy.
  • Move Up - click this button to move the currently selected pass in the Passes in this Routing Strategy list upward in the list. In other words, it will be used earlier in the routing strategy.
  • Move Down - click this button to move the currently selected pass in the Passes in this Routing Strategy list downward in the list. In other words, it will be used later in the routing strategy.

Tips

  • A defined routing strategy, and its constituent routing passes contained therein, is only applied when routing the entire board.
Found an issue with this document? Highlight the area, then use Ctrl+Enter to report it.

Contact Us

Contact our corporate or local offices directly.

You are reporting an issue with the following selected text
and/or image within the active document:
ALTIUM DESIGNER FREE TRIAL
Altium Designer Free Trial
Let’s get started. First off, are you or your organization already using Altium Designer?

If would like to speak with a representative, please contact your local Altium office.
Copyright © 2019 Altium Limited

In that case, why do you need an evaluation license?

If would like to speak with a representative, please contact your local Altium office.
Copyright © 2019 Altium Limited

Got it. You actually don’t need an evaluation license for that.

Click the button below to download the latest Altium Designer installer.

Download Altium Designer Installer

If would like to speak with a representative, please contact your local Altium office.
Copyright © 2019 Altium Limited

Please fill out the form below to get a quote for a new seat of Altium Designer.

By clicking “Get Your Free Trial”, you are agreeing to our Privacy Policy.
You may receive communications from Altium and can change your notification preferences at any time.

If you are on Altium Subscription, you don’t need an evaluation license.

If you are not an active Altium Subscription member, please fill out the form below to get your free trial.

By clicking “Get Your Free Trial”, you are agreeing to our Privacy Policy.
You may receive communications from Altium and can change your notification preferences at any time.

Why are you looking to evaluate Altium Designer?

If would like to speak with a representative, please contact your local Altium office.
Copyright © 2019 Altium Limited

You came to the right place! Please fill out the form below to get your free trial started.

By clicking “Get Your Free Trial”, you are agreeing to our Privacy Policy.
You may receive communications from Altium and can change your notification preferences at any time.

Great News!

Valid students can get their very own 6-month Altium Designer Student License for FREE! Just fill out the form below to request your Student License today.

By clicking “Get Your Free Trial”, you are agreeing to our Privacy Policy.
You may receive communications from Altium and can change your notification preferences at any time.

Got it. You can download a free Altium Designer Viewer license which is valid for a 6 months.

Please fill out the form below to request one.

By clicking “Get Your Free Trial”, you are agreeing to our Privacy Policy.
You may receive communications from Altium and can change your notification preferences at any time.

That’s great! Making things is awesome. We have the perfect program for you.

Upverter is a free community-driven platform designed specifically to meet the needs of makers like you.

Click here to give it a try!

If would like to speak with a representative, please contact your local Altium office.
Copyright © 2019 Altium Limited

Got it. You can download a free Altium Designer Viewer license which is valid for a 6 months.

Please fill out the form below to request one.

By clicking “Get Your Free Trial”, you are agreeing to our Privacy Policy.
You may receive communications from Altium and can change your notification preferences at any time.