The general circuit board production all will do Panelization operation, the purpose of as follows:
1. It is to increase the production efficiency of the SMT production line.
If you have a chance to visit the SMT production line, you will find that the biggest bottleneck of the SMT production line is actually in the "Solder paste printing" process, because no matter how big the PCB is, the printing cost the time almost around 25 seconds, that is to say, if the surface mount system takes less time than solder paste printing, it will be idle. Assuming that the time for printing a solder paste printing is 20 seconds, the pick & place followed by it takes only 15 seconds to complete, then this machine will have 5 seconds time is left, that is, idle is wasted 5 seconds. From the perspective of economic efficiency, this is a waste.
In fact, the speed of the surface mount system is very fast, as fast as one second you can pick & place several components. Some surface mount system even has several nozzles that can pick & place at the same time. Based on the number of parts on the mobile phone PCBA, if there are only single a board should take less than 10 seconds to complete all pick & place operations, so using PCB as a panelization to increase the number of components for the pick & place can increase the utilization rate of the surface mount system and improve efficiency. Of course, it is best to achieve "Line Balance" so that each device can be fully effective.
2. PCB panelization can save time, because you can pick and place multiple boards at once, and subsequent board testing also can greatly save the time when the board picking and placing in the fixture.
3. Some boards exhibit irregular shapes when they are designed. For example, this [L] shaped board, if it is made into a single board "Scheme 1," there will be a piece of scrap in the upper left corner, if it can be designed as "Scheme 2" panelization, then the waste can be greatly reduced, this is the concept of PCB board utilization improvement.
PCB Panelization
Disadvantages and limitations of PCB panelization
1. Although the PCB panelization has many advantages, but until all PCBA assembly operations are completed, it has to be de-paneled into a single board, then an additional process is required, which will increase the man-hours and increase the risk of collision parts.
2. If there are small components such as thin feet and 0201 on some boards, can’t put too many boards in one panelization, because there is a tolerance between the single boards. If there are too many boards, the tolerance may be too large to meet the accuracy of solder paste printing requires, maybe the final solder paste printing will biased, and cause soldering problem.
3. Some PCBs that are too thin are not recommended to have too many pieces, because the thinner the PCB, the easier to bow and twist, and the larger the number, the larger the size, both pick & place and reflowing are a crisis. Of course, this aspect can be overcome with a furnace carrier or a full-range carrier, but the carrier's expenses and increased labor costs have to be considered.
