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Circuit Board Pad Layout

Circuit Board Pad Layout

Circuit Board Pad Layout

(OP)
What are the possible manufacturing issues and drawbacks involved in using a pad layout that is exactly the same dimensions as the maximum tolerance of the footprint of the device being installed?  Can I get away with having a 7% overhang of the interior "heel" of the surface mount part relative to the pad?  Why should I follow an IPC recomended pad layout that takes up so much of my board space when the device will fit snug on a smaller layout?

RE: Circuit Board Pad Layout

1] there is no solder under the lead,  The only thing to connect is the pressure of the lead on the pad.  The electrical connection is through the solder fillet. The only thing holding the IC to the board is the solder fillet.
2] There is no way to inspect the solder joint for quality if it is all under the IC and you can't see it.
3] IPC gives guidelines for general production use. You should check with your production house on the minimum rules they need.

If you wish to hand build, inspect and test almost anything is OK, just don't try to sell it or support it as a product.

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