How to Judge the Quality of PCB at a Glance?
When we get a PCB board, how can we judge its quality is good or bad?
We can start from the following four aspects:
First, check the silkscreen of the board. High quality PCB screen printing is very clear, very three-dimensional. And solder resistance ink is smooth and uniform.
Second, check the PCB pad treatment. If it is a spray tin plate, examine whether the spray tin is smooth, IC foot position is neat.
Third, check whether the BGA pad is full and round.
When the PCB manufacturer with good quality handles and optimizes the BGA pad, the via hole will be treated with special treatment. And the exposure is also part exposure to ensure accurate alignment, so that the BGA is full and round.
Fourth, check the ink on the board. A good circuit board factory will choose famous brand’s ink, and pay great attention to the printing and baking process. The ink is a permanent protective film of PCB, which can protect the line from being easily wiped and damaged. There is no short circuit when insulating, and it is heat resistant, moisture-proof, preventing solder from adhering to the line and salt spray prevention.
For a reliable circuit board, ink will be relatively thick. According to the IPC standard, ink thickness needs to be ≧20μm. If the solder ink is too thin it will lead to copper exposure line; The factory with low process will also have problems such as IC bridge shedding, ink foaming, oil shedding, plug hole not full and transparent.
At present, the most famous ink manufacturers in the world are: TAIYO, Onstatic, Rongda, KuangShun, etc. TAIYO PCB ink is the best ink from the visibility and the quality of ink, its largest advantages: not easy to drop oil, can be without discoloration by reflow after 3 times. NextPCB are using the TAIYO ink to maintain the consistent high quality PCB manufacturing.