Hi Michael,

Yeah I agree that Max neck length only applying to a cline segment only is lame.

I recently filled out a post SR survey, and in the “suggested improvements” section (or whatever it was called), I gave them my “wish list”.

My list included the Max neck length applying to a whole cline. Maybe they’ve heard it enough and will be in 16.2.

Regards,

Gary

Hi Gary,

I was just cleaning out some of my icu-pcb threads and noticed your inquiry on the DRC checking for MAX neck length.  To the best of my knowledge the Maximum Neck Length setting still applies to cline segments only, and is not cumulative.  I have been complaining about this check  for several years now, but cannot provide a SR or PCR number for you to reference at this time. Please submit your SR if you have not already done so, and need this checking to apply to the entire net or Cline, and not just Cline segs.

Since this rule applies to a Net (or indirectly as a member of a Physical Class constraint), it certainly makes sense to do the DRC audit on the net or to provide some type of selectable control mechanism (ie. cumulative checking), or to check less (ie. non-accumulative).  DRC checking to only a single Cline segment makes absolutely no sense to me at all. (Maybe, it could be minimally acceptable if the neck length rule applied to a Cline of a net (pin-pin or a pin to via runner).

I am going to reinvestigate this rule in the 16.x tool suite to verify whether it has been corrected yet. I believe that the 16.2 tool release is on the road map for later this year. If not fixed in the 16.01 tools perhaps there is a shot for a 16.2 implementation, unless you truly believe that this is BUG and not an Allegro enhancement. 

Will try to update when I can.  

Sincerely yours,

Michael Baumstark

Sr. Staff Electrical Engineer / PCB Design, CID+
Motorola - Advanced Product Technology Center
8000 West Sunrise Blvd.  Mail Stop: 8E8
Plantation, FL USA 33322-9947
Intra: http://rprc.mot.com  ; http://pcbadvisor.mot.com
web: http://www.motorola.com
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Hey Dave,

Thanks for the reply.

Oh yeah, I’m on 15.5.1 also, XP Pro.

I think you misread my e-mail. It’s max neck length that I’m trying to use.

It seems to just apply to an individual cline segment, where I need to set a max neck length for a whole cline.

Gary

Version?

I am STILL on 15.51. Max net length works to the specified length on a cline.

Including multiple cline segments. You are seeing something different?

That would be good to know as that would be a big problem with us upreving.

dm

Hey guys,

Up until now, I haven’t had to worry about being even close to a max neck length spec.

Now I have a max of 500 mils that the neck length can be, and I’m going to have to use that up.

It looks like the “Max neck length” as specified in a Physical Constraint Set applies to a cline segment, not the full cline.

If I can only have a max length of 500 mils for the cline (all of the segments adding up to 500 mils), how can that be set up?

Thanks for any insight into this.

Regards,

Gary