Steve, This may sound strange but are you absolutely sure that the board is bad before you "repair it". In a previous life we had product that would fail at test but actually had no defect. The problem turned out to be poor connections at test. If you tested the boards they would fail at an alarming rate. When you disconnected and reconnected the boards they may pass or may fail. This finally lead us to the real problem. Jerry Dengler -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Steve Gregory Sent: Thursday, August 31, 2006 2:58 PM To: [log in to unmask] Subject: [TN] LLP (Leadless Leadframe Package) headaches... Good Afternoon my fellow esteemed TechNet-ologists, We're building a little double sided SMT board that has a National Semi 6-pin LLP (Leadless Leadframe Package) device on it. We call this little board a "Leaf" board because of it's shape: http://stevezeva.homestead.com/files/LLP.jpg The problem on this board is the LLP device. We've gotten quite a few boards back from test stating that the board failed test and that U4 needed to be re-reflowed. This is not the first time I've heard this prognosis from a test department to correct a problem with a board. Almost every time I've looked into this issue, I've not seen a problem with the solder joint, or a problem with the reflow profile, or anything else that you would naturally look at to try and explain why re-reflowing would correct the problem. Not to mention the fact that the parts that are right next to the questionable device are fine with no problems whatsoever. Yet when you re-reflow the part it will usually pass test the second time around. I've had this happen with QFP's, SOIC's, PLCC's, and now this LLP. Obviously it must have something to do with the solder joint, but what is it man?!?! I've scratched my head about this more than a few times. What does re-reflowing a perfectly good looking solder joint cause a board to pass test where it didn't pass before? -Steve Gregory- --------------------------------------------------- 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 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- 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 847-615-7100 ext.2815 -----------------------------------------------------