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#9932

Classification of moisture sensitive devices | 26 August, 1999

Having implemented the process of handling moisture sensitive devices our logistics department tries to classify all parts according to their moisture level. Going through datasheets wasn�t that helpfull, so does anyone know of a source for that specific information either depending on the packagetype or manufacturer and their specific parts ?

thanks in advance

Wolfgang

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#9933

Re: Classification of moisture sensitive devices | 26 August, 1999

| Having implemented the process of handling moisture sensitive devices our logistics department tries to classify all parts according to their moisture level. | Going through datasheets wasn�t that helpfull, so does anyone know of a source for that specific information either depending on the packagetype or manufacturer and their specific parts ? | | thanks in advance | | Wolfgang | | IPC/JEDEC J-STD-020A Moisture/Reflow Sensitivity Classification for Plastic Integrated Circuit Surface Mount Devices (Supersedes IPC-SM-786A)

The purpose of this standard is to identify the classification level of non-hermetic solid state surface mount devices that are sensitive to moisture-induced stress. They can be properly packaged, stored, and handled to avoid subsequent thermal/mechanical damage during the assembly solder reflow attachment and/or repair operation. This standard is used to determine what classification level should be used for initial reliability qualification. 20 pages. Released April 1999. Included in manual IPC-M-109.

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#9934

Re: Classification of moisture sensitive devices | 26 August, 1999

| | Having implemented the process of handling moisture sensitive devices our logistics department tries to classify all parts according to their moisture level. | | Going through datasheets wasn�t that helpfull, so does anyone know of a source for that specific information either depending on the packagetype or manufacturer and their specific parts ? | | | | thanks in advance | | | | Wolfgang | | | | | IPC/JEDEC J-STD-020A | Moisture/Reflow Sensitivity Classification for Plastic Integrated Circuit | Surface | Mount Devices (Supersedes IPC-SM-786A) | | The purpose of this standard is to identify the classification level of non-hermetic | solid state surface mount devices that are sensitive to moisture-induced stress. | They can be properly packaged, stored, and handled to avoid subsequent | thermal/mechanical damage during the assembly solder reflow attachment and/or | repair operation. This standard is used to determine what classification level should | be used for initial reliability qualification. 20 pages. Released | April 1999. Included in manual IPC-M-109. | |If your purpose is to find out what the sensitivity level of each device that you use is, and assuming that you have a managable number of different devices, get on down to your stockroom. Each sealed bag will have a label indicating the sensitivity level. Also, a search of this forum should yield good information.

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#9935

Re: Classification of moisture sensitive devices | 26 August, 1999

| | | Having implemented the process of handling moisture sensitive devices our logistics department tries to classify all parts according to their moisture level. | | | Going through datasheets wasn�t that helpfull, so does anyone know of a source for that specific information either depending on the packagetype or manufacturer and their specific parts ? | | | | | | thanks in advance | | | | | | Wolfgang | | | | | | | | IPC/JEDEC J-STD-020A | | Moisture/Reflow Sensitivity Classification for Plastic Integrated Circuit | | Surface | | Mount Devices (Supersedes IPC-SM-786A) | | | | The purpose of this standard is to identify the classification level of non-hermetic | | solid state surface mount devices that are sensitive to moisture-induced stress. | | They can be properly packaged, stored, and handled to avoid subsequent | | thermal/mechanical damage during the assembly solder reflow attachment and/or | | repair operation. This standard is used to determine what classification level should | | be used for initial reliability qualification. 20 pages. Released | | April 1999. Included in manual IPC-M-109. | | | |If your purpose is to find out what the sensitivity level of each device that you use is, and assuming that you have a managable number of different devices, get on down to your stockroom. Each sealed bag will have a label indicating the sensitivity level. Also, a search of this forum should yield good information. | | The problem is not to classify the parts itself it�s just setting the already defined but in most cases unknown level-information into the computersystem so that stockoperaters get a warning when handling moisture sensitive devices. Our stock is actually a mess and original bags are rare. It should also be used to check if incoming parts are properly packed and shipped according to their moisture level ( to often they are not ). It�s just hard work to check for each device, and their are a lot, the question is more for a listing available on the net referring package to level or part/manufacterer to level just to simplify the data input.

Wolfgang

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Tom Tellinghuisen

#9936

Re: Classification of moisture sensitive devices | 28 August, 1999

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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