differential pairs rules

[Carl_at_xrite]

Probably a dumb question, But I have had one hell of alot of trouble with the PADS/Blaze Differential pairs rules.

I set up my differential rules with my spacing impedance delay etc.
and PADS NEVER adheres to these rules at all.
I am always forced to manually go back and calculate the single ended impedance and then my differential impedance for USB, RS-422 etc. and manually route these the way I need them to be.

We dont own the EDC module, is this required for pads to actually adhere to these rules?
I know it wont flag the errors without the module.

Thanks all,
Carl

[randychase]

It is my understanding that Blaze in Ver4 does not support the high speed rules. That will be a module/option in Ver5 of Blaze.


Many people that require high speed rules now when autorouting have stayed with using Specctra instead because of this.

[Carl_at_xrite]

Randy,
Thanks for the answer, and yes I certainly transferred my support over to cadence for the upgraded specctra router.
Unfortunately, we did not purchase the required modules dfm,fst
etc. so its still just all done by hand.
I am not complaining other than the fact that pads/blaze didn't adhere to what I spent time inputting.
It's always been a hand route anyway in all the software's I used.
Anyway, Thanks again just confirmed my suspicions.

Carl

[Boarddesigner]

I cannot answer the question about edc.
But one thing you will want to check for is your rule hiarchy. In the past this has given me trouble. Make sure you dont have net rules overriding class rules, etc..

Haveagoodone

Boarddesigner