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 dependant upon the case material and the molding process. Because of this, you can buy a part from a Vendor who makes the device in two different factories in different parts of the world, and have two different MSLs for that same device. Another wonderful part about working with PEMs, is when you run across a small niche manufacturer, who doesn't even know that J-STD-020 exists. At that point, if they haven't classified the device, you have to, or default to saying the device is a level 6 classification. As a side note, we have a database of over 1000 devices utilized on our production floor, with the classifications noted. WE adopted this approach to try to be proactive, rather than reactive when the material hit the floor. We utilize this database to flag our kitting personnel that the devices are Moisture Sensitive, so if they are not packaged properly my engineers can go address the problem before we have latent field failures, (which are forbidden in our industry). We have found that not all distributors who supply us with material are properly repackaging the devices. The best way to get the information is to call the manufacturers and ask the Q departments for the classification. Some companies also post the information on their websites, but this is also hit or miss.
Tom Tellinghuisen
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