Thanks for posting, Steve. My concern? IPC-2221, Table 6-1 minimum electrical conductor spacing. For a low voltage assembly is 0.13mm. These solder balls are hugging one pad, so they aren't a problem. I probably agree that I wouldn't fail this particular board. If this solder ball trapped itself in between two pads, though, it is like a little stepping stone between the pads - the space on either side is less than the minimum clearance spec. Maybe I am applying this incorrectly? -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Steve Gregory Sent: July 21, 2008 11:54 AM To: [log in to unmask] Subject: Re: [TN] Solder balls Hi Genny! Sorry it's taken me a bit to get your picture posted, but I just got back from 2-weeks vacation and a week in Colorado going to a IPC-771/7721 instructor certification class, so I've been catching up on things this morning. But here is your picture: http://stevezeva.homestead.com/files/solderballs-QFN.jpg Myself, I wouldn't worry about them tiny solderballs. They probably aren't going anywhere, and besides if they did, they're so small what problem could it cause? Steve -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Genny Gibbard Sent: Monday, July 21, 2008 10:52 AM To: [log in to unmask] Subject: [TN] Solder balls Have you ever gotten a much better analytical tool available to you, and have it cause major panic due to what you can see now that you never saw before? We got a major fancy dancy brand new X-Ray. Now we see things like the attached picture. Steve, could I trouble you to post it for me? <<solderballs-QFN.jpg>> Our old X-Ray would have never seen this. Would you fail these solder balls? It is a QFN, 0.5mm pitch, 0.3mm pad width with a heat slug. I think trying to replace this device by hand would cause more trouble than we see right now. Genny --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 847-615-7100 ext.2815 -----------------------------------------------------