Altium High Speed Design Rule

[yy7d6]

I use Altium designer to auto-route my board, I set the Max Length -
High Speed Design Rule from Design>>Rules Menu. (Max Length = 38.1mm)
When the auto-routing is done, it seems that the Max Length rule i set
was not observed, i've tried to re-route many times but i got the same
result. It seems that the rule i set is not 'active' after all, any
ideas.

Thanks.

 

[Brad Velander]

yy7d6,
You need to read the autorouter details and any PDF docs that they have
online regarding the autorouter. I don't know about your particular length
rule but 'all' rules are not followed by the autorouter. So I suspect your
length rule may be one of the ones the autorouter doesn't follow.

otherwise, have you actually confirmed that your rule is valid and
properly formatted (syntax)? Try routing a trace manually and deliberately
exceed the rule length, then run the DRC check and confirm that it was
caught by the DRC? Then give the router a simple one net task that would
exceed the rule length (two pins X + some net length further apart than your
rule limit). If it routes it then it obviously doesn't follow the rule, the
way you wrote it. I know that a lot of people writing rules have difficulty
getting the right syntax or the right qualifiers. Have you thoroughly read
the approx. 3 PDF application papers dealing with queries, rules and rules
syntax?

You could also post your query to the AD Forum and you will likely get
an answer from Altium tech support or other users who have done the very
same thing. In this forum there are very few AD users and even fewer that
are not hobbiests.

 

[yy7d6]

When DRC the PCB after autorouting the board, it indeed shows the Nets
that violated the Rule.