Darshan, If you are asking about via-in-pad that technology exists. Like anything else it has trade-offs, not the least of which is fabrication cost. The issues that get addressed by people who do this successfully include: 1) Preventing the via from becoming a solder wick. 2) Ensuring the via does not create a coplanarity problem. Blind LASER vias tend to address both issues rather nicely, but at considerable cost. If you are interested, speak with your board fabrication and assembly shops about their capabilities. Steve. At 03:41 AM 11/11/2004 -0800, Darshan Mehta wrote: >Hi All, > > > >I have one general question regarding BGA routing. I have seen many BGA >boards and nobody puts via exactly below the BGA pad. Most of the times, >we generate Fanout outside the BGA pad. Is there is a specific reason for >that? I think we can save lot of space if we put via exactly below BGA >pad. Is there will be any problem if we put via exactly below the pad of >BGA? Thanks. > > > >Best Regards, > >Darshan Mehta > > > > >--------------------------------- >Do you Yahoo!? > Check out the new Yahoo! Front Page. www.yahoo.com > >------------------------------------------------------------------ >To unsubscribe from si-list: >si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field > >or to administer your membership from a web page, go to: >//www.freelists.org/webpage/si-list > >For help: >si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field > >List FAQ wiki page is located at: > http://si-list.org/wiki/wiki.pl?Si-List_FAQ > >List technical documents are available at: > http://www.si-list.org > >List archives are viewable at: > //www.freelists.org/archives/si-list >or at our remote archives: > http://groups.yahoo.com/group/si-list/messages >Old (prior to June 6, 2001) list archives are viewable at: > http://www.qsl.net/wb6tpu > ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu