The advantages and disadvantages of PCB surface coating

A. Electrolytic Ni/Au: This kind of coating is the most stable, but the highest price.

b. Impregnated silver plate (Immersiog AG) is not as good as gold plating coating, and it is prone to electromigration and leakage.

c. Electroless Nickel Immersion Au (ENIG), when the immersion gold process is unstable, it is easy to produce black discs.

d. Electroless Tin, lead-free tin-leaf plate is not yet fully mature.

e. hot air screed (Sn/Ag/CuHASL), the production process of this coating is not yet fully mature.

f. Organic Solderability Preservations (OSP), which are the cheapest, but worst performing. When using the OSP PCB board, pay attention to the time between two reflows and between the reflow and wave soldering. Because the protective film on the board pads is damaged after high temperature heating, the solderability will be greatly reduced.