In the process of purchasing electronic components, the most worrying thing for buyers is not the price, but the quality of the product. There are a variety of IC chips on the market, of all kinds, and without paying attention to the distinction, it is sometimes difficult to see the difference between various materials, whether it is true or false, new or refurbished. The following is a compilation of some methods to identify genuine and fake chips, for your reference.
Common chip counterfeiting methods
- Material A counterfeit material A
Original manufacturer's tailor loose material: the original packaging has been disassembled or is no longer available, but product functionality and yield may be lower due to storage time or handling process, etc.
Original manufacturer scrap or defective products: mainly products that have not passed factory inspection by the original manufacturer, such as scrap products after reliability testing, poor packaging quality, bad test products, etc.
Original material refurbishment: refurbished goods, old goods refurbishment.
Examples.
Left: Before the chip is opened, the IC silkscreen is: K9K1208U0A-YIB0 , 64M.
Right: After the chip was opened, the chip was found to be K9F5608U0A, 32M
- Material B counterfeits material A
Trademark and packaging counterfeiting: materials produced by informal manufacturers are counterfeited with the trademark and packaging of regular manufacturers.
Refurbished counterfeit goods: recycled electronic waste is reprocessed, such as grinding, foot pulling, foot plating, jointing, grinding, typing, etc., into new material. (The appearance of the chips is treated to make them look better, even to the point of being fake. Some even include vacuum bagging, making labels, foam, cartons, etc.)
Examples
By comparison, the Aeroflex IC pictured above is actually an IDT chip
How to identify genuine or fake chips
1.look at the surface of the chip whether there are traces of polished
Where the surface of the polished chip will have fine lines or even microscopic traces of previous printing, some to cover up the surface of the chip is also coated with a thin layer of paint, looks a little shiny, no plastic texture.
Simply polished, brutally finished
Finely polished, re-printed and laser-printed
2.Look at the printed word
The vast majority of chips nowadays are laser marked or printed with special chip printers, with clear lettering that is not conspicuous, not blurred and difficult to erase. Refurbished chips either the edge of the word by the cleaning agent corrosion and "jagged" sense or printed fuzzy, varying depths, incorrect location, easy to erase or too conspicuous.
In addition, the screen printing process has now been eliminated by the major IC manufacturers, but many chip refurbishment due to cost reasons still use the screen printing process, which is also one of the bases for judgment, screen printing words will be slightly higher than the surface of the chip, with the hand can feel a slightly uneven or astringent feeling.
However, it should be noted that, due to the recent significant reduction in the price of small laser marking machines, refurbished ICs are increasingly using laser marking, and some new chips will also use this method to change the word mark or simply re-type to "improve" the grade of the chip, which requires extra attention, and the method of differentiation is more difficult, you need to practice the "eyes of gold".
The main method is to look at the overall coordination, handwriting and background, pin the old and new degree of discrepancy such as word mark too new, too clear there is a greater possibility of problems, but many small factories, especially some small domestic IC company's chips are born so, which adds a lot of trouble for the identification, but the mainstream of the big factory chip judgment this method is still very meaningful.
In addition, recently the phenomenon of using laser marking machine to modify the chip mark is increasing, especially in memory and some high-end chips, once the location of the laser printer is found to have individual letters that are not aligned, the thickness of the strokes is not, it can be identified as Remark.
3.Look at the pins
Where bright as "new" tin-plated pins must be refurbished goods, the majority of genuine IC pins should be the so-called "silver powder feet", darker but uniform color, the surface should not be oxidation traces or "flux", in addition to DIP and other plug-in pins should not be scuffed traces, even if there are scuff marks should also be neat, the same direction and metal exposure is clean without oxidation.
Bright as "new"
"Silver powder feet"
4.Look at the production date of the device and the label number of the packaging factory
Remarked chips have the same label number on the front side, but sometimes the value is not normal or the production date does not match the device's character, and if the label number on the bottom side of the device is confusing, it also means that the device is Remarked.
5.Measure the thickness of the device and look at the edge of the device
Many of the original laser printing of the polished refurbished film (power devices mostly) because to remove the original mark, must be polished deeper, so the overall thickness of the device will be significantly less than the normal size, but not compared or measured with calipers, general inexperienced people or difficult to distinguish, but there is an alternative to recognize the method, that is, look at the front edge of the device. Because of the plastic sealing device injection molding must be "off the mold", so the device edge corner is rounded (R angle), but the size is not large, grinding processing is easy to grind this rounded corner into a right angle, so once the device front edge is a right angle, can be judged as grinding goods.
Calipers to measure the thickness
In addition, another method is to see whether the merchant has a large number of the original outer packaging, including the logo inside and outside the same carton, anti-static plastic bags, etc., the actual identification should be used in many ways, there is a problem with one can be identified as the quality of the device.
There are several points to identify the authenticity
A.look at the typing, the general refurbishment of the re-type sub with "banana oil" (chemical thinner) can erase the word generally for the refurbishment of goods, the original goods can not be erased.
B.look at the lead angle, the original goods pins are very neat and like a straight line, while the refurbished treatment is some of the feet are not neat and some crooked.
C.look at the positioning holes, observe the original goods positioning holes are more consistent, refurbished some of the depth or simply really polished flat, some if you look carefully can see the traces of the original positioning holes.
Conclusion: Fakes can't be prevented, it is recommended that you try to buy components from Seektronics to reduce the risk of buying fakes.
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