Hi Tom: Did you autoroute this board?
tr :) -----Original Message----- From: Tom Reineking [mailto:[EMAIL PROTECTED] Sent: Monday, July 26, 2004 1:48 PM To: Protel EDA Forum Subject: Re: [PEDA] first BGA layout Ralph, This is just an aside and not an explanation to your problem. I laid out a board with 3 BGAs are 0.75 mm and one 256 pin BGA at 1 mm spacing. Using .004" tracks with .004" spacing I was able to route the whole board on two signal layers with two power layers and no special vias, meaning all were through hole, .018" pad .010" hole. It did take some time and careful planing but at a huge PCB cost savings. Any time you go over 4 layers and start using fancy vias the cost accelerates geometrically. I your case that may not be an issue but in mine I had no choice. Don't forget to use gold flash for the BGAs (for the whole board is easier) to reduce manufacturing problems with soldering BGAs. Cheers, Tom Ralph Effinger wrote: > I am haveing trouble laying put an 8 layer board. I have a schematic, > board with chips, resistor,caps and one 256 bga. The bga has a 1mm > pitch. I have setup the layer stack mang. and the desing rules the best > I know how,{this is my first bga}. I layed out the board using blind or > buried vias. I am using protell 99se. after auto routing the board, the > vias all go from the top layer to the bottom not useing any blind or > buried vias. I,ve looked at the tutorials and book, and can find > nothing to help me. thank you! > > > > > > This message and any file transmitted with it may contain confidential information and is exempt from disclosure under applicable law. The information contained in this message and any file transmitted with it is transmitted in this form based on a reasonable expectation of privacy. Any disclosure, distribution, copying or use of the information by anyone other than the intended recipient, regardless of address or routing, is strictly prohibited. If you have received this message in error, please advise the sender by immediate reply and delete the original message. Personal messages express views solely of the sender and are not attributable to Biodex Medical Systems, Inc. * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * 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] * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
