In an ideal world, components would only be purchased from the original producer, a franchised distributor or an approved non-franchised source. However, this is not an ideal world. With the majority of components being counterfeited falling in the $1 to $10 range, this is a problem for all.
A simple approach to minimise counterfeit components passing through goods receipt to production is to create a component reference database so that reference components and images of known good components can be used for future comparison.
The following should be considered by engineers for inclusion in their company database. Reference component details should be obtained when a component is known to be going obsolete, on long lead times, difficult to obtain or found to be in circulation as a counterfeit product. Using a spreadsheet provides a simple way of storing data and links to other information.
Where components are being used in existing products or being considered in new products that are single source or subject to long lead times, they should be added to the component database. Where components are considered to be high risk, are knowingly purchased from a new source or the supplier has not been previously qualified, reference samples must be obtained for review and possible testing.
A golden board assembly is often held in manufacture as a reference for build quality or as an inspection reference and could be used by goods receipt staff. This is an ideal solution for OEM and also provides confidence for contract assembly staff as a working product is always the best reference.
X-ray inspection is a very powerful tool to examine a component or a batch of components without taking them out of their protective packaging. X-ray allows the lead frames, die size, bond wire type and package type to be identified. Figure 1 shows components inspected without opening the sealed MSD bags.
A guide to inspection of plastic ICs can be conducted by production staff after some hands-on training and a reference guide can be created for counterfeit avoidance with samples such as those in Figure 2.
The surface of the component body should be inspected: all surfaces should have a similar surface appearance and reflect light in a similar manner. If a surface has been modified/ground to remove previous marks there will be a difference in the surface, particularly around the markings. Figure 2b shows how the sharply defined moulding nodules have been flattened.
Any modification to the surface may change the appearance of surface features like moulding marks, laser marks and pin dimple indicators when compared with reference samples. In Figure 3, the surface of the plastic is as produced with sharp edges to the mould contours and no scratching on the surface of the mould contours.
A reference source/photo guide should be compiled of existing qualified manufacturers’ logos, packing labels, SMT reel labels and outer packing labels for use at goods receipt inspection. This may take time to compile but the sooner one starts, the better future problems are prevented.
Manufacturers should select and appoint an independent laboratory to conduct component testing when specialist tests may be required for independent verification. It makes sense that when someone is needed on call for support, company approval and financial issues have already been sorted in advance.
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