Appearance test refers to confirming the number of chips received, inner packaging, Humidity indicator, Desiccant requirements and appropriate outer packaging.
Second, the appearance inspection of a single chip, mainly include: Chip typing, years, Country of origin, Whether to recoat, Pin status, Are there any re-sand marks, Unknown residue, factorylogos position.

Open the lid（Unblock）Mainly use the instrument to corrode the package on the chip surface, Check for wafers inside, Wafer size, Manufacturer's logo, Copyright year, Wafer code, Can determine the authenticity of the chip.