Dec 24, 2019|General
PCB panelization is one of the most effective ways of producing small circuit boards in large quantities. By improving efficiency, this process can reduce costs, shorten manufacturing times, and otherwise make it easier to create devices the use printed circuit boards.
What is PCB Panelization
PCB panelization is the process of manufacturing small circuit boards as part of a single, broader array. This technique exists because many production machines cannot process boards below a specific size. Making the boards together, then breaking them apart along predetermined fault lines, solves this problem.
If you’re thinking about trying to panelize PCB parts, keep the following PCB panelization guidelines in mind.
Advantages of PCB Panelization
The most significant benefits of PCB panelization are high efficiency in mass production, improved product safety thanks to reduced shocks and vibration, and cost-effectiveness. Most fabricators strongly prefer using standard-sized processing panels, so creating arrays in the same size significantly lowers production costs.
Important factors to consider when Panelizing PCBs
Products have widely varying design requirements, including significant limits on size for internal circuit boards. Some boards also have unusual shapes, such as curves instead of the simple, popular rectangle. Panelizing PCB parts makes it possible to reduce wasted panel space and design panels that meet your needs instead of fitting to production requirements.
Components are an essential consideration for all printed circuit boards, but using panelization can open up material options. Small boards are weaker and prone to vibrations and shocks, so manufacturing them often requires using stronger, sturdier components that can withstand the shaking.
Panelization uses the sheer size of panels to minimize shocks and impacts, allowing you to use less-expensive parts without compromising the integrity of your circuit boards.
How big is a PCB panel? Production sizes vary, but most companies use a standard 18 by 24-in. PCB panel size.
Materials are often confused with components. In general, components are parts placed onto a circuit board, while materials cover the board itself. In most cases, panelization allows you to use more affordable materials. These savings are further augmented by reduced waste during production.
PCB Panelization Methods
What is V grooving in PCB, you ask? V-score panelization, sometimes known as v-grooving, involves removing v-shaped sections along the top and bottom of the panel. The depth of the groove varies, but most cuts go about 1/3 of the way on each side to make them easy to cut later.
Circuit boards are stronger than many people realize, so the remaining part requires machine removal.
V-score panelization requires a 0.05-in clearance from components to the center of the groove. Taller parts may need to be further away to give the cutter room to maneuver.
Jump-scoring is the process of not having a v-score go all the way across a panel. In most cases, manufacturers do this to leave the waste rails (the unprinted edges of the board) fully intact for the manufacturing process. Failing to jump-score could damage the array during production, so it’s usually best to leave half an inch or so at the ends of each panel.
Tab Routing Panelization
What is tab routing, you ask? Tab routing panelization focuses on making cuts while leaving perforated tabs that can be knocked out or cut apart later in production.
Tab panels require about 1/8 in. of clearance away from traces and surface-mounted parts. This is mainly because the cutting process can cause splintering or surface stress. Array weakness is a significant potential problem here, so you want to make sure you’re buying sturdy boards for this.
Most tab panels use five-hole knock-outs whenever possible. Failing this, three-hold patterns are also possible but must be placed much closer together to ensure overall structural integrity. Three-hole patterns are also useful in cases where tabs need to be placed underneath other parts.
Tabs should be placed as far from other components as possible. This may pose some difficulties in the design process, but the added stress can damage nearby components, so limiting the impact of production is essential to creating products that work long-term.
Perforations should be placed on one or both sides of a tab, not straight across the middle of the tab. The main reason for this is to minimize the size of protrusions from tabs, which ultimately helps with the overall integrity of a printed circuit board.
Array arrangements should involve as few tabs and movements as possible. Less processing is fundamentally better in PCB panelization, so the fewer passes your cutting machine needs to make, the better. With the right panelization, PCB circuit boards can use almost all of the available space on each board.
Solid Tab Panelization
Solid tab panelization is an alternative to the previous options and includes relatively large, solid tabs between each of the panels. This isn’t as popular because cutting thick tabs later is difficult and expensive, but it does provide better structural integrity during manufacturing.
Breaking Out PCB Boards
Breaking Tabs by Hand
Breaking tabs on a PCB panel by hand is possible, but usually a bad choice unless the boards are thin and designed for this purpose. Humans may put pressure on different areas of a board while breaking them, and this could render them unusable afterwards. Some people use a hook-shaped device to cut these tabs, although these are prone to moving back and forth.
Breaking Tabs by Machine
Breaking tabs by machine is usually more efficient than doing it by hand. Machines may physically break panels by holding them in place and using blades or cut them with more advanced tools like lasers.
Breaking V-Grooves by Hand
V-grooves are a little easier to break by hand than tabs are, especially because the pre-existing cuts are a weak point that usually breaks before anything else.
Cutting v-grooves with a saw blade (think of a pizza cutter) is usually more effective than doing it by hand. Some people use machines for this, such as depaneling routers that can accurately cut a groove without putting too much stress on the rest of the panel. Hiring the right manufacturer can ensure you receive well-cut boards.