Hi,
The number of PCBs I find that are UNSERVICEABLE because of the quest to make it SMALL, is increasing in the commercial world.
The manufacturer in the bit to get it small has custom made large scale integrated ICs or custom programmed control ICs.
Replacement IC's not available cos its OEM and 24 months old, obsolete, and they want you to update to newer model.
Or uses multilayered PCBs that somewhere develop an open circuit and short circuit to other tracks. Thus letting the smoke out.
Tom... 
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