I'd probably do it this way (top to bottom): sig gnd1 pwr1 sig sig gnd2 pwr2 sig
Assumptions: your highest-speed parts are on the top side. gnd1 and pwr1 are your main power rails for the highest-speed parts. Whatever you do, keep each gnd plane and it's matching pwr plane adjacent to each other - the distributed capacitance of this arrangement helps in decoupling the supply rails. This is in addition to your decoupling caps, not to replace them. I don't have anything to say about the dogbones. I'm still using cat treats... Best regards, Ivan Baggett Bagotronix Inc. website: www.bagotronix.com ----- Original Message ----- From: "Michael Biggs" <[EMAIL PROTECTED]> To: "'Protel EDA Forum'" <[EMAIL PROTECTED]> Sent: Monday, June 02, 2003 4:20 PM Subject: [PEDA] eight-layer stackup > Anyone have a preferred method of stackup guidelines of web references to > layer stackups for 8 layers using four power planes and four signal layers? > I am torn between two methods being that I have two internal power planes. > Thanks for any help! > Also I have a couple of BGA's on this layout and when I run (using > Protel99SE) my DRC everything is great other than the "dogbones" I had to > route to the via on all the unused pins of the BGA. Any way to create rules > for this so I do not get violations during DRC? > Thanks again! > > MichaelB * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * To post a message: mailto:[EMAIL PROTECTED] * * To leave this list visit: * http://www.techservinc.com/protelusers/leave.html * * Contact the list manager: * mailto:[EMAIL PROTECTED] * * Forum Guidelines Rules: * http://www.techservinc.com/protelusers/forumrules.html * * Browse or Search previous postings: * http://www.mail-archive.com/[EMAIL PROTECTED] * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
