The appearance test is mainly to observe the accuracy of the typing, year, origin and manufacturer's logo of the screen printing part of the device through a microscope, whether there are signs of re-coating, re-polishing and renovation, whether there are unknown residues on the surface of the device, and whether there are signs of re-adjustment of the pin. Secondly, physical scraping/chemical wiping is used to further verify whether there are signs of coating on the chip surface.

Contents of appearance inspection:

1. Package inspection includes: label, outer package integrity, braid, etc

2, the contents of the package detection include: scratches, dirt, damage, not full, overflow, etc.

3, the content of printing detection includes: error, offset, leakage, multiple printing, fuzzy, tilt, displacement, hyphenation, secondary coating printing, no font, etc.

4. The content of pin detection includes: pin missing, pin damaged, pin spacing, pin width, pin bending, pin span, pin length difference, pin standing height, pin coplanarity, pin tilt, pin oxidation, re-alignment, re-planting balls, etc.