What are the most common attributes to recognize counterfeit parts?

What are the most common attributes to recognize counterfeit parts?

It is hard to recognize counterfeit parts as a whole. However, some common attributes will help us to distinguish between genuine and non-genuine parts.

Marking

Observing the part marking is beneficial for identifying counterfeit electronic components in some instances. The quality of the original part marking will be good but, the quality of remarking will be poor. The logo also does not match the original standard.

Sometimes the letters or digits repeat in part marking. Different fonts, irregular alignments, and variable sizes display indications of remarking. In the following image, the size of the two “C” is different, and the bottom line size is different than the other lines.

Part marking in counterfeit electronic components

Part remarking is also determined by comparing the samples having the same date code and lot code. Orientation of the part marking and bars are different in the following image.

Different orientation in part marking

Texture

The surface texture is a crucial factor for determining counterfeit components. The texture should be smooth and consistent. If it is rough and inconsistent, then it’s considered modified. Here is an example of laser burn and grain structure inconsistency in the marking.

Consistent Vs inconsistent surface texture

Comparison between good and reworked part number

Another thing to observe is the mold marks. Usually, mold marks should be smooth. But after alteration, they look grainy or contaminated.

Difference between smooth and grainy mold mark

Mold marks will not occur on all parts, and some of them may appear to be textured. It will depend on the manufacturer and the part number. There is one more factor that proves the resurfacing. Generally, the top and bottom parts of the component will have the same texture since they develop due to the coating or the molding of the organic material. But if it differs, then the component is said to be compromised.

Difference between the top and bottom surface texture

The high-magnification test inspects surface texture. Items are visible and easily recognizable during this inspection.

Conditions of contacts in counterfeit electronic parts

Conditions of the contacts is a significant factor in recognizing counterfeiting. The leads should be straight, and the distance between them should be equal. Observing the marks on the leads is essential to decide if they are the result of the normal tooling, insertion, or previous usage. Some flip chips consist of balls having test indentions formed as a result of factory testing. The packages having deformed balls signify re-balling.

Additionally, scratches, contamination, irregular plating, and corrosion are the factors that show counterfeiting.

Generally, at the tips of the leads, there is a presence of copper where the lead was formed. If there is no presence of copper, then it shows the re-tinning.

Disfigured lead

Condition of leads (corroded leads)

It is also possible to have damaged leads as a result of mishandling or shipping. In that case, those parts are not forged. There should be proper documentation to trace any such abnormalities occurring on the component.

Dimensions

Comparing the physical dimensions of the part with the datasheet specifications also detects counterfeit parts. This includes using a micrometer or other measuring instrument to check the dimensions. The thickness of the part will be discrepant with the datasheet due to reworking.

Blacktopping

Blacktopping refers to the coating that covers the area, which is removed by sanding or through any other method for employing a new part number. It is inspected by acetone test. If the acetone removes this coating, then the parts are said to be unauthentic. The following observations will indicate whether the part has been remarked:

*Change in the surface texture

*Irregularities

*Elimination of the black ink

*Visible previous markings