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] Hi Les! There are a number of systems out there for BGA re-balling. Some use mini-stencils to print paste, or flux on to the BGA, then use a template to locate the spheres on to the BGA pads. Then there is a system that utilizes BGA pre-forms that have the spheres imbedded into a water-soluble paper for whatever pattern BGA you have that makes things pretty easy: _http://www.winslowautomation.com/bga.asp_ (http://www.winslowautomation.com/bga.asp) This link will detail to you all the steps that are used to re-ball a BGA. They also perform this as a service. That being said, for class 3 product, I would be a little hesitant to use re-balled BGA's, because of all the thermal cycles that the part is going to be subjected to. The first cycle is the intial reflow cycle during assembly. Then the part is going to be removed, the second cycle. The BGA's pads will need to be cleaned-up to remove the old solder so that new spheres can be attached, a third cycle. The spheres will then need to be attached, a fourth cycle. Then the device will have to be attached to the assembly once again, a fifth cycle. I know that with some of the latest Xilinx BGA's where the cost can make you cr*p your pants ($2500+), wanting to salvage them becomes a real consideration. But, with all the thermal cycles that you will be putting these parts through during the re-balling and BGA re-attachment process, I would be hesitant depending on them during critical applications where their function is vital. All the above is for eutectic sphere BGA re-balling. For high lead content spheres (such as those on Ceramic BGA's), I have no knowledge. I do know that the previous link I provided, will direct you to the same re-balling service that offers that as well...it's not cheap. The only time I have re-balled BGA's and used them is with class 2 commercial product... never with class 3. -Steve Gregory- November 9, 2004 We have an OEM who has some de-laminated PWA'S with some BGA'S installed. He wants to salvage the parts and have them re-balled. I have no direct experience in this area. How does one re-ball a BGA? What types of BGA can be re-balled? What are the pros and cons on re-balling? Is this an acceptable repair method for Class 3 product? --------------------------------------------------- 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 -----------------------------------------------------