PCB (printed circuit board) depaneling, also called singulation, is the procedure of removing a lot of smaller, individual PCB Depaneling from a larger multi-PCB panel produced during processing. The depaneling process was created to be able to increase throughput of PCB manufacturing lines as circuit board sizes reduced. At CMS Laser, our depaneling process has the advantage of speed, pin-point accuracy, no tooling cost or wear, no part induced stress, with no cutting oils or other waste.
Demand Driven by Size
As technology continues to evolve, the gadgets we use become a little more advanced and frequently decrease in size. This reduced size requires smaller PCBs. With no set standard for PCBs, every board is designed for a particular item. Therefore, this process for depaneling separate boards coming from a multi-image board is different. Production factors including stress, precision and cleanliness are paramount to keeping board defects as low as possible.
PCBs are typically produced in large panels containing multiple boards at the same time, but can be produced as single units if need be. The depaneling of PCBs process can be fully automatic, manual, or semi-automatic. There are numerous methods used, including laser PCB depaneling, within the electronics industry. Let’s examine the things they are:
The punching method is the method of singular PCBs being punched out of the panel by using a unique fixture. The punching fixture has sharp blades on one part and supports on the other. Another die is required for each board and dies must frequently be replaced to maintain sharpness. Even though the production rates are high, the custom-designed fixtures and blades demand a reoccurring cost.
Boards are scored over the cut line on sides to reduce overall board thickness. PCBs are subsequently broken from the panel. Each side in the panel are scored to your depth of approximately 30 percent in the board’s thickness. Once boards have been populated, they could be manually broken from the panel. You will find a strain put on the boards that may damage a number of the components or crack the solder joints, in particular those close to the edge of the board.
Wheel Cutting/ Pizza Cutter:
The “pizza cutter” technique is a manual alternative to breaking the net after V-scoring to slice the rest of the web. Accuracy is crucial, as the V-score and cutter wheels has to be carefully aligned. You will find a slight level of stress on board that could affect some components.
Laser depaneling can be performed on boards requiring high tolerances. Depaneling occurs without physical contact, with no mechanical stress, and is also adaptable to reduce requirements by way of a computer controlled process. Laser depaneling is suitable for installation in surface mount technology (SMT) lines or with board unloaders/loaders for standalone operation.
Most Laser PCB Cutting Machine are routed leaving the person circuits attached to the panel frame by narrow tabs that are subsequently broken or snapped to singulate the circuits. Routing can take up significant panel area because of wide kerf width of the physical bit.
Laser routing supplies a complete software-controlled process without reliance on any mechanical dies or blades. Laser routing can cut any shape path including curves and sharp corners. The cut kerf width could be under 20 microns, providing exceptional accuracy.
Laser routing can be performed using either:
High-power CO2 laser (~10µm wavelength)
The CO2 laser can thermally cut through FR4, glass fibers as well as other rigid and flex circuit substrates at comparatively high-speed though with noticeable heat effect on the fringe of the cut for the majority of substrates.
Solid-state UV laser (355nm wavelength).
The UV laser, using a considerably smaller focused spot size, ablates the panel material with significantly less heat and a narrower kerf width. However, as a result of lower power levels, the cutting speed is significantly vboqdt compared to CO2 laser and the cost/watt of UV lasers is higher than that of CO2
In general, businesses that are sensitive to char and fine debris over the cut line will employ the UV laser while users who clean the circuits after singulation can be helped by the larger speed in the CO2 laser.
Laser systems for depaneling play an integral role in the future from the PCB manufacturing industry. As need for Motorized PCB Depaneling carry on and parallel technology trends, such as wearables and Internet of Things (IoT) devices, the need for systems that increase production line speed and reduce costs for manufacturer may also carry on and rise.
Within our Applications Development Lab, we assist each client to ascertain the ideal laser and optics configuration for a manufacturing process.
Within this three-part series on PCB depaneling, upcoming posts will discuss the advantages and challenges of PCB depaneling, combined with the evolution of PCB depaneling with laser systems.