Electronics Forum | Sat Aug 28 08:41:12 EDT 1999 | Tom Tellinghuisen
Wolfgang, We also tried to find generic 'guidelines' for Moisture Sensitivity levels. It would be a perfect world, if you could say that all PLCC84's were level 4 devices. Unfortunately it is not that easy. Moisture sensitivity levels are
Electronics Forum | Tue Jan 02 14:50:37 EST 2001 | fmonette
Dear Vicki, If you decide to use high temp paste, I suggest that you verify the rating of the components, especially for moisture-sensitive devices which are normally qualified at peak reflow temperatures of 220-235C. The specified floor life will
Electronics Forum | Mon May 13 10:37:56 EDT 2002 | fmonette
The other important issue relates to moisture sensitive devices (MSD). If you have MSDs on the first side, you need to track the remaining floor life of the components on the partially assembled boards between the first and second reflow. Contrary to
Electronics Forum | Tue Dec 04 13:23:05 EST 2001 | fmonette
Hi Steve, It sounds like your product will have many moisture-sensitive devices on both sides. You should be aware of the additional controls that are required to insure the reliability of these components in a double-side reflow application. The
Electronics Forum | Wed May 15 12:55:11 EDT 2002 | fmonette
Hi Dave, The short answer is "not any significant amount" of moisture is removed during reflow. The temperature excursion is much too short. If you look at the physics of moisture diffusion inside a package you will see that only the surface moist
Electronics Forum | Wed May 15 09:46:15 EDT 2002 | davef
Francois: How much moisture does a typical reflow cycle remove from popular SMT packages?
Electronics Forum | Fri Nov 02 08:30:40 EST 2001 | fmonette
For double-side reflow boards, take note that if you have moisture-sensitive components on the first side, you will need to track their remaining floor life up to the final reflow. This is because the reflow process is too fast to effectively remove
Electronics Forum | Tue May 26 07:46:26 EDT 1998 | Peter H. Cote
We currently bake plastic SMT parts in accordance with the IPC guidelines for moisture sensitive parts. Because we have double-sided boards that are subjected to either an aqueous or semi-aqueous cleaning process, we do a 24 hour bake at 125 deg. C
Electronics Forum | Sun May 17 13:46:30 EDT 1998 | Steve Gregory
Hi All! I've been reading this conversation which prompted me to break out the IPC-SM-786A from the IPC manuals from our parent company in Maryland sent us (we're just starting up in California). It's the Procedures for Characterizing and Handling of
Electronics Forum | Fri May 15 10:27:16 EDT 1998 | Justin Medernach
| | We had some failures on an IC package that the manufacturer has put down to moisture inside the package, leading to popcorning. | | This seems a bit odd, the package is a PLCC 84 which is quite thick. I have only seen this problem on thin package
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