What are the causes of PCB board welding defects?

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What are the causes of PCB board welding defects? [Copy link]

What are the causes of PCB board welding defects?

In order to ensure the overall quality of PCB boards, excellent solder should be used during the production process to improve the solderability of PCB boards and prevent warping and defects. So, what are the causes of PCB board welding defects?

1. The solderability of the circuit board hole affects the welding quality.
If the solderability of the circuit board hole is not good, it will cause cold soldering defects, affect the parameters of the components in the circuit, cause unstable conduction between the components and the inner layer wires, and cause the entire circuit function to fail.

2. Welding defects caused by warping
Circuit boards and components warp during the welding process, and defects such as cold solder joints and short circuits occur due to stress deformation. Warping is often caused by temperature imbalance between the upper and lower parts of the circuit board. For large PCBs, warping can also occur due to the weight of the board itself.

3. The design of the circuit board affects the welding quality.
In terms of design, if the size of the circuit board is too large, although welding is easier to control, the printed lines are long, the impedance increases, and the cost increases; if it is too small, the heat dissipation decreases, the welding is difficult to control, and adjacent lines are prone to mutual interference. Therefore, the PCB board design must be optimized:
a. Shorten the connection between high-frequency components and reduce EMI interference.
b. Heavy components should be fixed with a bracket and then welded.
c. Heat dissipation issues should be considered for heating components, and thermistors should be kept away from heat sources.
d. The arrangement of components should be as parallel as possible, which is not only beautiful but also easy to weld, and suitable for mass production. The best design of the circuit board is a 4:3 rectangle. The wire width should not change suddenly, and large-area copper foil should be avoided.

The above are the causes of PCB board welding defects. I hope it will be helpful to you.

annysky2012

Good PCB, first design, second management

就某个水呀

annysky2012 posted on 2021-5-8 20:42 A good PCB is first designed and second managed

That's right

专业PCB

Material reasons account for a large proportion