Agree with Steve. multiple reflow will "take off" your product life. I believe Agere did study regarding device life vs multiple reflow. The reliability of those parts are significantly shortened after multiple reflow. (not mention if you reflowed at lead free temperature...). If the DFR is budgetted one extra reflow in the design, you can either use it at re-balling or use it at board level, but not both.... (normally, you design for board 3 reflow, top smt, bottom smt plus one connector...for board... you can do it for 5 reflow if you like, at "realiability cost"..). if your product is one shot deal, like fire arm, who cares... if your product is lasting 15 years, every bit counts....if it is life support, you better not have anything "strange" to eat the safety margin....(Since you can not predict where the device is going to end up, usually it is "no rework")... jk (my 1.66 cents) -----Original Message----- From: TechNet [mailto:[log in to unmask]]On Behalf Of Steve Gregory Sent: Wednesday, November 10, 2004 9:20 AM To: [log in to unmask] Subject: Re: [TN] Re-balling of BGAs Hi Dave! You're not worried about the multiple thermal cycles? -Steve Gregory- Hi Steve! Reballed area array components (BGAs, CSPs, FCs) are also appropriate for Class 3 products provided a strict procedure is followed. We have created an internal process procedure, using either preforms or mini-soldersphere placement equipment, to reball components that are critical in terms of cost or schedule. Issues such as moisture content, thermal processing impact, ESD, and solderability need to be addressed in the procedure but utilizing reballed area array components is achievable for the Class 3 world too. Dave Hillman Rockwell Collins [log in to unmask] --------------------------------------------------- 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 -----------------------------------------------------