Dave Sharples wrote: > > If this is so how do you fanout fine pitch BGA components or even 35 mil > pads on 50 mil pitch. Remember, the IPC rules are guidelines only. I understand that most of the people on those committee's were also assembly people more than designers, & hence understandable why the rules might lean heavily that way. If you want your design bullet-proof, follow the guidelines (& hence don't use BGAs - yeah right!). Reality then sets in & you then elect to break the rules advisedly only where you really need to (i.e. around the BGA). If you were really wary, you could break out the outer two rows of the BGA by the IPC recommended hole-pad clearance to further reduce the minimal risk but, speaking as a designer, I would prefer not to do that (takes up *lots* of area etc). -- Dom Bragge CID "The pink building" Production Manager Level 1, IBC Bldg KLAXON IQA Australian Technology Park bh+61-2-9209-4404 Eveleigh 1430 NSW fx+61-2-8374-5030 (Sydney, AUSTRALIA) www.klaxoniqa.com Directions to Klaxon IQA http://www.whereis.com/search/email_map_redirect.jhtml?id=138778 --------------------------------------------------------------------------------- DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF DesignerCouncil. To set a vacation stop for delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site http://www.ipc.org/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------