----- Original Message ----- From: "Mike McMonagle" <[log in to unmask]> To: <[log in to unmask]> Sent: Wednesday, February 04, 2004 12:29 PM Subject: [TN] 0805 Pad Geometry > Looking for feedback on what pad geometries are being used these days > for standard 0805 chips. We are primarily a high-rel, low volume high > temp alloy shop, but have recently pulled in a standard Sn63 board in > volume that the customer is looking for a little layout assistance on. > Pad dimensions are way too large and pad-to-pad spacing too tight, > contributing to big fillets and squeeze balls at the component edges. It > could be worked through aperture changes in the stencil, but the fab is > being spun for another reason anyway so now's a good time to fix 'em up. > Seems that almost every component manufacturer is calling out there own > pad preferences, many of which are contradictory to IPC design > guidelines. Also, any new comments on the pros and cons of using pads > that are slimmer than the termination width of the component? TIA for > the insights.... > > Mike > Mike, I looked at the 0805 part in my library and it has 50mil X 40mil pads spaced 80mil apart (center to center). Those measurements are X,Y if the part is viewed vertically. I don't think I tailor that part very often, and it has always worked without any incidents ever being reported to me. Good luck. Richard --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------