1.Make sure there are no polished traces on the chip's surface.
A polished chip will have fine lines or even micro marks from the previous printing. The surface of the chip is sometimes covered with a thin layer of paint, giving it a little sheen and a plastic-free feel.
2. Notice the printing on the chip.
A refurbished product is generally the original product unless it has been re-typed (white), and the re-typed (white) is generally able to be erased with chemicals. Original products cannot be erased. The refurbished chip has "jaggy" edges that are corroded by cleaning agents, or the printing is fuzzy, different in depth, improperly positioned, easy to erase, or too conspicuous.
3. Examine the pins.
The pins on the original product are very neat and look like straight lines, while the feet on the refurbished product are a little crooked and irregular. Whenever tinned pins are as bright as "new," they must be refurbished. Pins on genuine ICs should be dark and uniform in color, with no traces of oxidation or "flux" on the surface. In addition, the pins of plug-ins such as DIPs should not have scratches; even if there are (repackaged) scratches, they should be neat, in the same direction and the exposed metal should not have oxidation.
4. Check the production date of the device and the label on the packaging.
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. While the label of the unmarked refurbished piece is confusing, and the production time is different.
5. Observe the positioning hole carefully.
The positioning holes of the original products are relatively consistent. Some of the refurbished products have different depths, and some can still be identified as the originals if look closely.
6. Measure the thickness of the device and check the edge.
It is easy to grind the rounded corners to a right angle during grinding, so the front edge of the device is right-angled once, and so may be considered as polished goods because plastic packaged products must be "released" after injection molding.
7.Identifying your suppliers.
Whether to sign contracts.
Check the company name on the local business website.
Whether there is a fixed telephone line and whether the fixed phone can be connected.
Find out if there is an office in the given location, if a factory exists, and who to contact.
Check whether there is a website and whether the information on the website is consistent with the information provided.
The chip needs to be inspected, the payment must be made before shipping, and whether the payment is made from a company account. Otherwise, you may receive a pile of bricks.
A product warranty should be provided. If the problem can be solved conveniently.
