glop top popcorn

We are reflowing boards that have glop top components mounted on them. Do glop tops have the same moisture sensitivity as fine pitch? Should we be baking the boards prior to reflow?

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| | We are reflowing boards that have glop top components | mounted on them. Do glop tops have the same moisture | sensitivity as fine pitch? Should we be baking the boards | prior to reflow? | |If your glob tops are PBGAs, they are likely very moisture sensitive. Check on how they are supplied from your vendor. All manufacturers and any reputable reseller will properly package any moisture sensitive component in a vacuum packed, heat sealed bag with desiccant packs and a RH indicator card inside. The label on the bag will state the sensitivity level (3,4...) indicating the allowable time out of the bag. If the components are handled properly before reflow you don't have to worry. If they are not, it would be advisable to bake the component before mounting and reflow. The primary reason to bake the board would be if you wanted to remove, reball and reuse the moisture sensitive component. Check out IPC J-STD-033 for handling procedures. John Thorup |

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