The single-sided plug hole of a tin-plated circuit board is prone to plugging and copper leakage. When pcb soldering, the solder plugged in the hole will be sprayed out, forming a solder ball stuck on the pcb pad, affecting the solder paste. Printed.
Then why there is a single-sided plug hole, the industry has two processes, the traditional “printing solder mask → spray tin → plug hole” and “printed solder mask and plug hole → spray tin.” The former process is more complicated, there are two “wet processes”, the production cycle is longer, but generally there is no problem of plugging (related to the pore size, more than 0.3mm will not hide the tin beads), while the latter 70% of the semi-plug hole There is a problem that the orifice is blocked.
Therefore, to prevent the problem of plugging holes in the single-faced plug hole of the tin plate, the processing method should be specified.
What measures should we take for a single-panel plug?
(1) Designated by the traditional “printing solder mask → spray tin → plug hole” process.
(2) Change the design and use the small window soldering process. Another advantage of opening the small window solder mask design is that there is no organic residue in the hole.
This happens only on the sprayed tin (HASL) board. ENIG, Im-Ag, Im-Sn, OSP, etc. are all chemical reactions and do not cause plugging.
① Prepare a actual product surface soldered pcb assembly board . Because printed solder paste and the PCB assembly board without soldering cannot fix the test end of the thermocouple, it is necessary to use the soldered actual product for testing. In addition, the test sample cannot be used repea...
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