Not necessarily a study, but recently I evaluated the board level requirements.
For the most part Class 2 PWBs are equivalent to Class 3.  The largest differences are cosmetic.
Now this is not what you find on assemblies.  The differences between the classes are much larger.
I am not sure why they do not correspond, but if you are a board builder and someone wants Class2 to get their price down, look at the spec.  It may cost you just as much to inspect it.
BTW, most people do not manufacture boards based on their "Classification" .  Generally, if there is Class 3 work being done, everything is built the same, it is the inspection and the documentation that is different.
If you are designing boards, look at Class 2.  You may be able to use it for your product.



Richard MacCutcheon
BFGoodrich Aerospace
Manufacturing Engr.,Launch Vehicles
505-938-5151

>>> Dennis Guy-Sell <[log in to unmask]> 09/26/00 05:07PM >>>
The written distinction between Class 2 and Class 3 is straightforward.  But
have there been reliability studies conducted comparing Class 2 vs. Class 3
printed wiring boards, and comparing Class 2 vs. Class 3 electronic
assemblies?  If the studies exist, are they available?

Thank you.

Dennis Guy-Sell
Quality Engineer

EDO Electro-Ceramics
2645 South 300 West
Salt Lake City, Utah 84115
Phone   801-486-7481 ext. 219
Fax     801-484-3301
Email   [log in to unmask] 

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