Hi Michael, I'll tell you a few things about removing the unused annular rings in general. - First of all my opinion is that it's better not to do that. It depends on your layer structure of course but they are used for hole plating and are good to be there. - If you still want to remove them, it's preferable to do that when generating the gerbers or by modifying the gerbers. This will keep your DRC happy and the clearance to all other copper areas (traces, polygons, pours or planes)will be the same. If you delete these pads in the design, then the CAD program will calculate the clearance between the polygon and the hole itself and if your fab has problems with the layer registration, you might end up with shortages in the power planes. - The only reason to delete these pads during the design is if you need more space to place traces but that should be done case by case. Sometimes modifying the ring to oval is better than removing it completely.
I'm sorry I don't have Allegro with me right now but I'd propose to delete these pads at the gerber level and only if it's absolutely needed. Mira --- "Robison, Michael R NAVSEA" <[EMAIL PROTECTED]> wrote: > Mira, > > I'm sorry! Allegro. I'm copying your email to > Brian Heeter, who has the > motherboard in Allegro. I posted because I am > familiar with Protel and > subscribe to the PEDA users group. > > Jim McGrath wrote and suggested looking for a > feature like Protel's ability > to delete all the unused annular rings when the > Gerbers are produced, but > we are wanting to spread out some double traces > running between thruholes, > and I think we'd run into trouble with our design > rules checker waiting > until Gerber generation to delete the rings. > > Thank you for writing, Mira. We appreciate any > advice you might give us. > > Thanks again, Michael > > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] Behalf Of > Mira > Sent: Thursday, March 09, 2006 11:22 > To: Protel EDA Discussion List > Subject: Re: [PEDA] OT: Cadence thruhole question > > > Michael, > > Can you be more specific? Do you mean Allegro or > Orcad? > > Mira > > --- "Robison, Michael R NAVSEA" > <[EMAIL PROTECTED]> wrote: > > > I apologize for the off-topic post, but I haven't > > had any luck getting a response on > > the Cadence newsgroup. We use Protel for all our > > boards that we don't anticipate a > > need for signal-integrity analysis, but we've used > > Cadence on a 16-layer motherboard > > we are working. > > > > We need to turn off the annular ring generation on > > all thruholes on layers that have > > no electrical connection. With 7000 thruholes, we > > would like to not have to do it on > > a hole-by-hole basis. An off-list response would > be > > appreciated. > > > > Thank you, Michael > > > > > > > ____________________________________________________________ > > You are subscribed to the PEDA discussion forum > > > > To Post messages: > > mailto:[email protected] > > > > Unsubscribe and Other Options: > > > http://techservinc.com/mailman/listinfo/peda_techservinc.com > > > > Browse or Search Old Archives (2001-2004): > > > http://www.mail-archive.com/[email protected] > > > > Browse or Search Current Archives (2004-Current): > > http://www.mail-archive.com/[email protected] > > > > > > > __________________________________________________ > Do You Yahoo!? > Tired of spam? Yahoo! Mail has the best spam > protection around > http://mail.yahoo.com > > > ____________________________________________________________ > You are subscribed to the PEDA discussion forum > > To Post messages: > mailto:[email protected] > > Unsubscribe and Other Options: > http://techservinc.com/mailman/listinfo/peda_techservinc.com > > Browse or Search Old Archives (2001-2004): > http://www.mail-archive.com/[email protected] > > Browse or Search Current Archives (2004-Current): > http://www.mail-archive.com/[email protected] > > > ____________________________________________________________ > You are subscribed to the PEDA discussion forum > > To Post messages: > mailto:[email protected] > > Unsubscribe and Other Options: > http://techservinc.com/mailman/listinfo/peda_techservinc.com > > Browse or Search Old Archives (2001-2004): > http://www.mail-archive.com/[email protected] > > Browse or Search Current Archives (2004-Current): > http://www.mail-archive.com/[email protected] > > __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com ____________________________________________________________ You are subscribed to the PEDA discussion forum To Post messages: mailto:[email protected] Unsubscribe and Other Options: http://techservinc.com/mailman/listinfo/peda_techservinc.com Browse or Search Old Archives (2001-2004): http://www.mail-archive.com/[email protected] Browse or Search Current Archives (2004-Current): http://www.mail-archive.com/[email protected]
