Multi-up PCB Panel
Multi-up PCB Panel means only one design and a few boards in a panel. If the individual PCB is small such as 50mm, we can panelize a few, like 3 or 4 pcs, in the shorter edge to ensure the best PCB panel size. This multi-up PCB panel is applicable for Prototype PCB assembly and high volume. If the PCB is greater than 200mm in the long edge, we can multiple panelize a few PCBs on the short edge. But as always, the panel must still have 5-14mm waste-tabs around the edges with 3 fiducials on at least 2 waste-tabs and 4 tooling holes upon the actual SMT assembly requirement.
Waste-tabs on PCB panel edges
Waste-tabs, also called technique tabs, should be added to the PCB Panel. The waste-tabs with 5-14mm will increase the PCB cost of the Panel, but in some cases, it is worth the increasing cost. In high volume PCB assembly orders, the PCB assembly company would like to consider the cost savings of only adding waste-tabs on two edges of the Panel rather than all 4 edges. But this requires evaluation by our engineer on specific printed circuit board assembly project. The purpose of the waste-tabs around the Panel is to make sure that if there are any parts that hang over the edges, they have clearance from machinery, and board support if they are heavy or thin easy to break. If particular long connector is found in custom PCB assembly, the PCB assembly factory should extend the waste-tabs on that edge to be longer to support that extra part of the connector outside of the PCB edge.
In SMT assembly house, technicians or other people hold the PCBA on hand by hand through grabbing the PCB waste-tabs. Without anything to hold, it’s easy for fingers to get into solder paste or pre-reflowed, post-placement parts and thus ruin the product. What’s more, the waste-tabs enable us to use fixtures in whole PCB assembly and testing processes. For Flex Circuit Assembly, there is nothing to adhere the tape for fixtures. Besides, when the PCB requires 2 waste-tabs on the panel, adding waste-tabs on the long edge of the panel will be more economy than that on short edge.