Fourteen Important Features of High Reliability PCB (2)

6. The tolerance of CCL meets the requirements of IPC4101ClassB/L
Benefit:
Strictly controlling the thickness of the dielectric layer can reduce the deviation of the expected value of the electrical performance.

The risk of not doing so:
The electrical performance may not meet the specified requirements, and the output/performance of the same batch of components will vary greatly.

7. Define solder mask materials to ensure compliance with IPC-SM-840ClassT requirements
Benefit:
“Excellent” ink to achieve ink safety and ensure that the solder mask ink meets UL standards.

The risk of not doing so:
Poor quality inks can cause adhesion, flux resistance and hardness problems. All of these problems can cause the solder mask to detach from the board and eventually lead to corrosion of the copper circuit. Poor insulation properties can cause short circuits due to accidental electrical continuity/arcing.

8. Tolerances defining shapes, holes, and other mechanical features
Benefit:
Tightly controlled tolerances improve product dimensional quality – improve fit, form and function.

The risk of not doing so:
Problems during assembly, such as alignment/mating (problems with press-fit pins are only discovered when assembly is complete). In addition, the mounting into the base can also be problematic due to increased dimensional deviations.

9. The thickness of the solder mask is required, although IPC has no relevant regulations.
Benefit:
Improved electrical insulating properties, reduced risk of peeling or loss of adhesion, and increased resistance to mechanical shock – no matter where the mechanical shock occurs!

The risk of not doing so:
A thin solder mask can lead to adhesion, flux resistance and hardness problems. All of these problems can cause the solder mask to detach from the board and eventually lead to corrosion of the copper circuit. Poor insulation properties due to thin solder mask, can cause short circuits due to accidental conduction/arcing.

10. Defines appearance requirements and repair requirements, although IPC does not define.
Benefit:
Safety is created with care and care in the manufacturing process.

The risk of not doing so:
A variety of scratches, minor damage, patching and repairs – circuit boards work but don’t look good. In addition to the problems that can be seen on the surface, what are the unseen risks, the impact on assembly, and the risks in actual use?

11. Requirements for the depth of the plug hole
Benefit:
High quality plug holes will reduce the risk of failure during assembly.

The risk of not doing so:
Chemical residues from the gold immersion process may remain in the holes that are not full of plug holes, causing problems such as solderability. In addition, there may also be tin beads hidden in the holes. During assembly or actual use, the tin beads may splash out and cause a short circuit.

12. Designate the brand and model of peelable blue glue
Benefit:
The designation of peelable blue glue avoids the use of “local” or cheap brands.

The risk of not doing so:
Poor quality or cheap peelables may foam, melt, crack or set like concrete during assembly making the peelables unpeelable/non-effective.

13. Implement specific approval and ordering procedures for each purchase order
Benefit:
The execution of this procedure ensures that all specifications have been confirmed.

The risk of not doing so:
If the product specification is not carefully confirmed, the resulting deviation may not be discovered until the assembly or final product, and then it is too late.

14. Sets with scrapped units are not accepted
Benefit:
Not using partial assembly can help customers improve efficiency.

The risk of not doing so:
Defective kits require special assembly procedures, and it is possible to assemble the known bad board if it is not clear to mark the scrap unit board (x-out), or to isolate it from the kit. Waste of parts and time.