Richard Sumner wrote: > David, > > Talk to your assembler before you invest time in this. The paste mask > becomes a metal stencil for applying the solder paste. So donuts will > not work (the donut hole is unsupported).
Actually my idea was to make the width of the track greater than 2x the radius of the arc so I would end up with a "filled donut". (For example if I want a 30 mil opening in the paste mask, I could use a 20mil wide arc with a radius of 5mil.) However, what I have just tried that seems a bit simpler is to use a pad and a via (gee a via in a pad!) where the pad is TopLayer only and the via is set for tenting. Do an update free primitives after import to the PCB and viola... > Big BGA's are a pain. If you could only get the designer > to use only the two outer rows ....... Unfortunately, I am the designer on this one and I have to go 10 rows deep (31x31 with all positions used! At least the inner most pins are power and GND. Actually the 4 corners are missing so its only 957 pins.) In the past I have always used "dogbone" connections between BGA pad and via, but this time there are requirements for via-in-pad (which I do not like or trust, however the customer is "always right" if he persists in a decision that he has been warned against!). But, I really wish for better control of the pad stacks (including ALL layers). David W. Gulley Destiny Designs * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * 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] * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
