What Is a PCB Panel?And What Are Its Advantages?

1. What Is a PCB Panel?

The PCB panel refers to the assembly of several circuit boards onto one large board, in order create a plate.

After the PCB design has been completed, the circuit board and the components must be assembled in the SMT patch assembly line. The SMT factory will specify what size board is best for the assembly line. The tooling used to fix the circuit boards cannot be fixed if the board size is too big or small. What happens if the size of the circuit board is less than the factory’s specifications? The circuit boards will be combined into one single piece. The panel will improve the efficiency and speed of wave peak welders and high-speed patch machines.

PCBs are often “several in one” boards. For example, 2 in 1, 4 In 1, 6 In 1, etc. This means that multiple single boards have been assembled into a large board.

You will see that the largest bottleneck in the SMT line is the “Solder Paste Printing” process. This is because, no matter what size the PCB, it takes almost 25 seconds to print. If the time taken by the expensive fast patching machine or general-purpose patching machine is shorter than the solder paste printing machine, then there will be idleness. Idleness is a loss from the economic perspective.

The speed of the machine is so high that it can punch multiple parts in a second. Some patch machines have multiple nozzles which can punch several parts simultaneously. If there are only one board and a limited number of components on the PCBA, then it shouldn’t take more than 10 seconds to perform all the patching operations. Making the PCB into a jigsaw can improve the efficiency of the patch machine by increasing the number of parts. It is important to “line balance” each device so that it can be used fully.

In some cases, the majority of parts are placed on one side of the PCB while only a few parts are on the opposite side. You can use a mirror board to increase the number on one side, but it will be limited.

2. PCB Panel Division Method

The panels must be assembled during the design phase. After the final processing, we need to separate plates. Three traditional methods are used.

1) V-CUT

When several plates are combined (or if the same plate is used), the PCB cuts a V shape slot into the plates. It can come off when used. This is the most common method today.

Features: A V-shaped groove is suitable for PCBs that have a straight edge. This includes rectangular PCBs. It is the most popular choice for SMT board because of its neat edge and low processing cost.

2) Direct Connection

Direct connection is when the milling machine runs between the boards or inside the board. It is similar to digging out. This type of board must be divided using a board machine, and not a direct small circuit board connection.

Features: If you want to split a board without unevenness or burrs, then a board-splitting machine is the best option.

3) Stamp Hole

A stamp hole connection connects the plate with the plate by using a small, circular hole.

Features: Suitable for special-shaped board, wide range of applications, the only disadvantage is a small burr.

3. Advantages of PCB Panels

1) Increase the Efficiency of SMT Production

Which is faster, 6pcs or 1pcs? Panel increases our production efficiency but also allows for faster delivery. Faster delivery means a shorter time to market and a competitive advantage.

The panel design and the process side design eliminate the need to open treatment equipment. This allows you to reduce the time required for prenatal preparation, so you can deliver faster.

The number of transmission boards and the cycle frequency can be decreased by processing multiple PCBs into one large PCB at a time. This allows for the production of more circuits in less time. It also improves the efficiency and lowers the price of the PCB. This is important, especially for large-scale electronics manufacturers.

2) Maximize Plate Utilization Rate

It is possible that the PCB design has created many unusable boards.

As the figure below shows the cost difference between the two methods of paneling is very large.

We can reduce costs and waste by combining small or irregularly-shaped PCBs.

It is important to consider this when pursuing production processes that are cost-effective.

3) Reduce Production Difficulty

The production process is made easier by reducing the complexity of the PCB to a simpler structure. It is important to improve production efficiency and ensure product quality.

Multiple boards can be combined if the company is small, the projects are numerous, the number of layers, the production and processing technologies are the same. The board factory may charge a combined fee, but it will be much less expensive than processing multiple projects separately.

The patch factory will only do one project if there are multiple projects to be made into Boys. This saves a lot of money on the cost.

4. What Is the Purpose of Making a Break-Wway on a PCB?

Many people call this break-away or coupon because it can be broken directly. It is similar to the discount coupons in convenience stores. It is not recommended that the board edges are broken by hand for quality reasons. To reduce the stress created when board edges are broken, machine equipment (Scoring and Router) can be used to remove them. This will help to prevent tin cracking on parts or board.

PCB board edges are designed to aid in PCBA assembly. SMT is a highly automated production line, with the board being transported via belts and chain. It was a clever idea. The board edge’s main purpose is to transport this board with these belts and chain.

You can, of course, leave some space around the board if you wish. It is recommended to leave at least 5.0 mm around the board because the iron chain for the reflow oven needs to be positioned deeper. This allows you to avoid designing the board edge.

The edge of the PCB can also be used for other purposes:

Place tooling holes: After the SMT process, “tooling holes” may be used to help position the board for ICT or FVT tests. This will prevent the needle bed from moving and the test point.

Detect the position of the circuit board: Each machine in the SMT line has a sensor that detects whether there are any subsequent boards to make sure only one panel works. The patchwork of the previous board will not be completed, and it will cause the other panel to crash into the first panel, causing chaos. Some single boards will have a hollowed-out appearance at the location where the SMT production lines sensor detects them, which is usually the upper left corner at the front edge. The edge of the board is now a good way to detect solids by the sensor.

Positioning optical points: If space is limited, you can place the fiduciary marks at the edges of some boards. However, it’s recommended to also have the positioning points near the fine foot of the board on the parts’ tray to improve the accuracy of the patch.

5. Rules and Methods for PCB Panel

1) Understand the Panel’s Maximum and Minimum Sizes

The maximum and minimum sizes of the panels should be clearly defined according to the requirements of each patch factory. The maximum size depends on the factory’s processing capacity. Generally, PCBs less than 80X80mm require a panel.

2) Panel Meets DFM DFA Requirements

After the fixture, the panel must be fixed and not easily deformed. The surface flatness of the PCBA patches processing shall be met by the split grooves that are between the panels.

3) Reduce the Stress on the Components

The PCB panel should be designed to avoid component cracking due to segmentation stress. Pre-engraved lines on the panel can reduce the deformation and warping of the panel.

4) Design the Plate as Closely as Possible to a Square

It is important to determine the size and shape of the panels according to the project. The appearance should also be as square as possible. Use of 2×2 or 3-by-3 panels is highly recommended. Mirror board is not recommended unless absolutely necessary.

5) Avoid Profile from the Edge Connector

Rotating the panel + edge of the process is the solution to the problem when the outline of the panel-side connector exceeds the interference. This will prevent poor quality collision parts being transmitted or handled after welding.

6) Make Sure That the Bottom Point of the Large Plate Has a Margin of at Least 3.5 mm

The panel design must be such that the edge of the large baseplate should be at least 3.5 mm away from the plate. (The minimum distance of the PCB is 3.5 mm). Also, the diagonal bases of the large baseplate and the points of the front or back of the panel cannot be symmetrical. This can prevent PCBs being reversed into the machine by the identification function.

7) The Thickness of the PCB Plate Is Not Less Than 1 mm

The PCB middle strength support skeleton – glass fiber cloth V-cut part is affected by the PCB thickness less than 1.0 mm.

8) The Gold Finger Edge Cannot Be Added to or Connected With the Process Edge

If there is a gold finger on a PCB, it is usually placed on the outside of the plate in the direction opposite to the splint. The edge of the gold finger cannot be added or connected to a process edge.

6. PCB Panel Design

Multiple factors must be taken into consideration in the design of a PCB panel.

In order to meet the requirements of the PCB panel design, it is important to consider other factors.

1) Consider the Product’s Characteristics

First, the analysis of product characteristics should be comprehensive, including circuit layout, power consumption, and signal transmission.

It is possible to operate the panel system with greater stability and reliability by avoiding the performance degradation and interference caused by a complex circuit structure.

2) Balance the Plate Utilization Rate with Production Efficiency

The production capacity and efficiency should be taken into consideration when selecting the number of panels and the method to use. This will ensure that there are no additional bottlenecks in the manufacturing process.

A good layout can reduce waste and have a positive effect on the environment and sustainable development.

3) Ensure Product Reliability and Safety

Special attention is given to the effect of panels on signal integrity and circuit stability.

Avoiding the crossing of and interference with signal lines can maximize the performance of the circuit.

In order to design high-frequency circuits or sensitive components that can operate reliably and stably under different working conditions, a more precise layout and analysis is required.

4) Consider the Manufacturing Costs and Processing Difficulties of SMT Production

It is also important to consider the manufacturing costs and processing difficulties of SMT.

To avoid creating unnecessary problems, the pooling scheme must be coordinated with SMT’s production process.

A comprehensive cost evaluation, including labor, material and equipment costs, is also required to determine whether the panel design can be made cost-effectively.

We work closely with the production line during the entire PCB panel design process to ensure the design scheme is compatible with the needs of the product.

7. Disadvantages and Limitations of PCB Panel

Increase Your Workflow:

After all PCBA assembly, the PCB still needs to cut into single boards (de-panel). It adds a process that increases the number of working hours, and the likelihood of a collision when transporting the boards.

Balance the Number of Panels and Cost:

The number of panels must not be excessive if there are too many fine feet on some boards or small parts. They cannot also be too large or wide, as the board will shrink and expand, causing a tolerance between individual boards. The tolerance could be too high if there are too many boards. This would make it impossible to meet the accuracy standards of the solder paste printing. The solder paste may be biased and cause problems with soldering.

It is not a good idea to use too many panels on PCBs that are too thin, as the deformation will be greater. The board will get wider if there are too many panels. This will make it difficult to patch and reflow. This can be avoided by using a full-process or furnace carrier. However, the added cost and time of labor must also be taken into consideration.

8. Summary

PCB panel design in general is a complex, comprehensive process that requires engineers to think holistically at various levels.

By carefully designing, you can not only improve the production efficiency and reduce costs but also ensure the reliability and performance of your product.

The design of PCBs will continue to be important in the future, as science and technology continues to develop and the manufacturing industry grows.