When it comes to the authenticity of components, it is nothing more than to distinguish whether the components are original or new in bulk. The bulk new goods mentioned here are refurbished or disassembled parts, which are processed and reprocessed devices, so the industry generally refers to them as bulk new goods. At the same price, everyone wants to buy new, brand-new functional devices, so it requires some common sense to distinguish which are original new products and which are what we call new parts.
1. Check if there are any polished traces on the surface of the integrated circuit chip. The surface of the polished chip will have fine lines or even the micro marks of the previous printing. Some of them are covered with a thin layer of paint on the surface of the chip, which looks a bit shiny and has a texture without plastic.
2. Look at the printing. Most of the current chips use laser marking or use a dedicated chip printer to print, the writing is clear, neither conspicuous, nor blurry and difficult to erase. The refurbished chip either has a "jaggy feeling" on the edges of the writing that is corroded by the cleaning agent, or the printing is fuzzy, different in shades, incorrectly positioned, easy to erase, or too conspicuous. In addition, the silk-screening process has already been eliminated from major IC manufacturers, but many chip refurbishments still use the silk-screening process due to cost reasons. This is also one of the judgments. The silk-screened characters will be slightly higher than the surface of the chip, and you can feel the slight unevenness when you touch it by hand. Or feel astringent. However, it should be noted that due to the recent sharp drop in the price of small laser marking machines, more and more refurbished ICs are using laser marking. Some new films will also use this method to change the word mark or simply reprint to improve the chip’s performance. Grade, this requires special attention, and the distinction method is more difficult, you need to practice "eye-eyed golden eyes." The main method is to look at the overall coordination. The handwriting is not consistent with the background and the old and new levels of the pins. For example, the word mark is too new, and there is a greater possibility of problems with over-clearing. However, many small factories, especially some small domestic IC companies The chip is born like this, which adds a lot of trouble to the identification, but it is still very meaningful to judge the mainstream chips. In addition, recently there are more and more cases of using laser marking machines to modify the chip markings, especially in the memory and some high-end chips. Once it is found that there are individual letters and pens with uneven thickness in the laser printing position, it can be determined It's Remark.
3. Look at the pins. All tinned pins that are as bright as "new" must be refurbished. Most of the pins of genuine ICs should be so-called silver powder pins, with darker color but uniform color, and there should be no traces of oxidation on the surface. In addition, the pins of plug-ins such as DIP should not be scratched, even if there are scratches (only after repackaging), the scratches should be neat, in the same direction, and the exposed metal should be smooth and non-oxidized.
4. Look at the production date of the device and the label of the packaging factory. The label of the original product, including the label on the bottom of the chip, should be consistent and the production time should be consistent with the device product, while the label of the unremarked refurbished piece is confused and the production time is different. Although the front label of the Remark chip is the same, sometimes the value is unreasonable (such as what is labeled "Geely number") or the production date does not match the device product. If the label on the bottom of the device is messy, it also indicates that the device is Remark.
5. Measure the thickness of the device and look at the edge of the device. Many original laser-printed polished and refurbished sheets (mostly power devices) must be polished deeper to remove the original marks, so the overall thickness of the device will be significantly smaller than the normal size, but if you don’t compare it or measure it with a caliper, generally less experienced people still It is difficult to distinguish, but there is a flexible way to see through, that is, look at the front edge of the device. Since the plastic packaged device must be "released" after injection molding, the edge corner of the device is round (R angle), but the size is not large. It is easy to grind the rounded corner into a right angle during grinding, so the front edge of the device is once right-angled , Can be judged as polished goods.
In addition, another method is to see if the merchant has a large number of original outer packaging, including cartons with the same logo inside and outside, anti-static plastic bags, etc. In actual identification, multiple methods should be used. If there is a problem, it can be determined The quality of the device. If there is a writing chip that we cannot judge with the naked eye and experience, we can use a writing tool, such as a magnifying glass and a digital magnifying glass to polish the refurbished chip table, and there are tiny holes that are difficult to see with the naked eye. We must use Equipment to observe! There are a few important points:
1. Look at typing. Generally, the refurbished ones (white characters) that can be erased with chemical thinner are generally refurbished products, and the original ones cannot be erased.
2. Look at the lead angle. The pins of the original product are very neat and look like a straight line, while the feet of the refurbished product are irregular and a little crooked.
3. Look at the positioning hole. Observe that the positioning holes of the original products are relatively consistent. Some of the refurbished products have different depths or are really polished at all. If you look closely, you can see the traces of the original positioning holes. In actual work, we must carefully observe and observe. Some counterfeit craftsmanship is quite high, so we must be very cautious in purchasing!