As we visit our customers we get questions about different methods of detection and which ONE is the best.  It would be so nice if there was a litmus test for counterfeits and we could just use one technique.  I get the feeling many would like to get an answer from us that, say… X-Ray is the catch all, or a curve trace.  Fortunately, but also unfortunately, good old physical inspection of the parts is still the best way to catch most counterfeits.  The fortunate aspect is that it is the least expensive for equipment.  The unfortunate part is that you need a very well trained eye to detect many of the characteristics. 

This group of parts we received today is an extreme case of putting together the pieces to make a determination.  First we noticed a slight ghost marking on some of the pieces.  Could it happen at a manufacturer?  Sure, it would not be the first time a manufacturer changed a marking on a part.  But you can’t stop there.  You have found a clue that you need to follow further.  Next we see parts with different indents/mould cavities on the package.  We also noticed differing lead shapes.  That certainly would not happen at a manufacturer.  At least not if they are the exact same lot code.  Then we start to find clues of re-work, such as; dirt, unknown substances, chipped packaging, and sanding marks from the removal of the old part number.  Now we can skip all of the expensive tests.  If the parts looked perfect, but the source was in question, we may begin the more expensive testing with X-Ray, XRF, Decapsulation, Curve Trace Analysis, etc. using the same type of detective style method, looking for a few different anomalies to determine authenticity.