Acceptable standards for solder beads on PCBA products

In the process of PCBA processing, there will always be some tin beads left on the surface of the PCBA board, and the industry will have an acceptable standard for the size and number of tin beads on the PCBA board. The following are the acceptable standards for PCBA appearance inspection standards (referred to as national standards) for the solder beads on the surface of PCBA.

Tin beads can accept standards:

1.The diameter of the tin beads does not exceed 0.13mm

2. The number of solder beads with a diameter of 0.05mm-0.13mm within the range of 600mm2 does not exceed 5 (single-sided)

3. The number of tin beads below 0.05 is not required.

4. All solder balls must be wrapped with flux and cannot be moved.

5.The tin beads have not reduced the electrical gap between different network conductors to less than 0.13mm

Note: Except for special control areas

Tin beads rejection criteria:

Any non-compliance with the acceptance criteria is judged as rejection.

Remarks:

1. Special control area: Tin beads visible under a 20x microscope are not allowed within 1mm around the capacitor pad on the differential signal line on the gold finger end.

2. The existence of tin beads itself represents a warning to the manufacturing process. SMT chip manufacturers should continuously improve the process to minimize the occurrence of tin beads.

The PCBA appearance inspection standard is the most basic standard for electronic product acceptance. Depending on the requirements of different products and customers, the acceptable requirements for tin beads will vary. Generally, it is based on national standards and combined with customer requirements. To determine the standard.