Hi Francois, What about spare parts / assembled cards for replacements in systems / machines after 10, 15 years. Best Regards ROKAH Reuven Francois Monette <fmonette@COGISC To: [log in to unmask] AN.COM> cc: Sent by: TechNet Subject: Re: [TN] Expiry time in vacuum package <[log in to unmask] > 29/04/03 09:18 PM Please respond to "TechNet E-Mail Forum."; Please respond to Francois Monette Hi ROKAH, I do not have this kind of data but I know a few suppliers of dry bags that might be able to help. I have forwarded your questions to get their feedback. As far as J-STD-033A is concerned, the shelf life for previoulsy dry components in a sealed bag with desiccant is at least one year when that package is stored in an environment at less than 40C/90%RH. This one year minimum shelf life is only for information purposes since the shelf life might be significantly longer based on the actual conditions where the sealed bag is stored. The status of the package and the components is based strictly on the reading of the Humiditiy Indicator Card when the package is opened. If the HIC is still within the specified limits (less than 10%RH) then the components are considered dry enough to be processed and reflowed, within their specific floor life of course. If the HIC reading exceeds the specified limit, then the components must be baked to reset their floor life (Ref : J-STD-033A, section 5.5.1). I am not aware of any standard guidelines for long term storage of moisture sensitive components in sealed bags. Regards, Francois -----Original Message----- From: [log in to unmask] [mailto:[log in to unmask]] Sent: Tuesday, April 29, 2003 1:32 To: Francois Monette; [log in to unmask] Subject: Re: [TN] Expiry time in vacuum package Thanks Francois Monette, Do you have any data regarding shelf life for spare parts (assembled PWB or active components) in dry bag with desiccant and complying with J-STD-033A? There is any table for end of life evaluation of components / assemblies in the sealed packages? There is any Spec. / written procedure for maintaining the goods in the sealed packages? Best Regards ROKAH Reuven Francois Monette <fmonette@COGISC To: [log in to unmask] AN.COM> cc: Sent by: TechNet Subject: [TN] Expiry time in vacuum package <[log in to unmask] > 28/04/03 08:31 PM Please respond to "TechNet E-Mail Forum."; Please respond to Francois Monette As you can tell the question of shelf life and storage conditions for electronic components and assemblies is a very complex issue. One of the criteria to consider is the fact that most ICs are classified as moisture-sensitive devices (MSD). This means that the components are shipped from the manufacturer in a sealed dry bag with desiccant and a warning label. The label includes two important pieces of information relative to the safe storage of these components. First the seal bag date provides an indication of the actual shelf life of the sealed bag itself. Since a Moisture Barrier Bag is never perfectly hermetic, it will absorb some moisture from the ambient air and eventually the desiccant will saturate and moisture will exceed the safe level for the components. By definition, the packaging guidelines included in the joint IPC/JEDEC standard J-STD-033A guarantee a shelf life of at least 12 months at conditions of less than 40C/90%RH. This is conditional upon using the proper type of dry bag (Water Vapor Transmission Rate WVTR is less or equal to 0.002 gm/100in2 in 24 hres ar 40C) and the proper amount of desiccant (Ref. J-STD-033A, section 3.3.2.2). The second important information is the maximum floor life of the components once they are removed from the sealed bag, prior to reflow. This can vary from a few hours to a few months. An important consideration is the fact that if you are re-sealing components that have previoulsy been exposed to ambient conditions, the moisture gradient that was previoulsy absorbed will continue to diffuse towards the die interface and may eventually exceed the critical limit. In other words, re-sealing MSDs in a dry pack does not necessarily stop the floor life clock and your components may expire while they are stored in a re-sealed bag. This would be applicable in the case of assembled PCBs being placed in re-sealed dry bags for example. Of course it is always possible to re-set the floor life clock by completely baking the components and boards prior to re-sealing them in dry bags. Once again the guidelines for baking components and boards are included in J-STD-033A. On the subject of vacuum, this is not required for dry storage of MSDs. A simple heat seal with the proper quantity of desiccant will provide the protection required. I suggest that you familiarize yourself with J-STD-033A since the Moisture-sensitive components will most likely be your most critical components. This document is a free download at www.jedec.org. Once you define a process that meets the requirements for MSDs, everything else should be much simpler. I hope this information is helpful, do not hesitate to call or e-mail if you have any questions on the above. Francois Monette Cogiscan Inc. Tel : 450-534-2644 [log in to unmask] www.cogiscan.com ------------------------------ Date: Sun, 27 Apr 2003 10:27:35 +0300 From: Reuven ROKAH <[log in to unmask]> Subject: Expiry time in vacuum package Hello Technet forum, Pls reply how long Active component of assembled PCB / system can be stored in sealed / vacuum package before use / operating the system / component. Best Regards ROKAH Reuven --------------------------------------------------- Technet Mail List provided as a free 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a free 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a free 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------