Since the break-up tab consumes more PCB CCL and increases the overall cost of the PCB, it is necessary to balance economy and manufacturability when designing the PCB break-up tab. For some special-shaped PCB boards, the original PCB with 2 or 4 break-up tabs can be greatly simplified through the method of panelization. When designing the panelization method in SMT processing, it is necessary to fully consider the track width of the SMT placement machine. For panelization with a width of more than 350mm, it must to communicate with the process engineer of the SMT supplier.
The main reason for leaving the break-up tab is that the track of the SMT placement machine is used to clamp the PCB to flow through the placement machine, so the components that are too close to the track side are sucked in the suction nozzle of the SMT placement machine and mounted to the PCB, the phenomenon of bump occurs, and the production cannot be completed, so certain break-up tab must be reserved, such as 2-5mm and so on. Similarly, it is also applicable to some plug-in components to prevent similar phenomena during wave soldering.
The flatness of the PCB production break-up tab is also an important part of the PCB production. When removing the PCB production break-up tab, the break-up tab is ensured to be flat, especially for PCB that require extremely high assembly accuracy. Any uneven burrs will cause the mounting holes to shift, which will bring great trouble to subsequent PCBA assembly.