PCB nowhere to “place”? A few industrial PCB interconnection skill points, help you solve it!

[Introduction]As we all know, PCB board design is a basic skill that Electronic design engineers must possess, and it is also a touchstone for testing the technical strength of hardware engineers. However, if you want to advance to the system-level design of electronic products in addition to the board-level design of “drawing the board”, then the interconnection design between PCBs has become a skill point that must be mastered.

The reason why we need to consider the interconnection between PCBs is easy to understand: Electronic systems are becoming increasingly complex, and considering the requirements of system scalability, it is obviously impossible to implement all functions on a large PCB, so it is It needs to be divided into parts, different functions are implemented on different PCBs, and then these “small” PCBs are connected to each other to build a complete large system.

But this is easy to say. In actual combat, how to make the PCB in its place through an optimized layout and place it in the system reasonably is often a troublesome thing that bothers engineers. In the chassis of many devices, we can see PCBs that have been placed hastily due to “nowhere to fit”.

There are many technical issues that need to be carefully considered in order to reasonably “place” the PCBs used so that they are in their proper places and can be reliably interconnected with each other.

#1 First, the issue of maximizing space utilization must be fully considered, which requires the use of high-density, compact interconnect solutions as much as possible in the design.

#2 Secondly, the scalability of the interconnection solution also needs to be considered to ensure that it can provide enough product options to meet diverse design requirements and provide greater design flexibility.

#3 Furthermore, the ease of assembly and maintainability on site is also very important, which can greatly reduce the cost and labor intensity of equipment maintenance and overhaul, and also help reduce the occurrence of personnel operating errors.

#4 In addition, in applications in complex environments such as industries, there are usually higher requirements in terms of EMC and safety protection.

#5 Finally, the final design needs to be aesthetically pleasing, orderly, and in compliance with design specifications. This is the higher realm of “engineer aesthetics”.

If you want to achieve the above design goals, you need PCB solution products to provide assistance. Today, we will introduce two commonly used and very practical solutions: board-to-board connectors and modular electronic housings.

Board-to-Board Connector

Hardware engineers must be familiar with board-to-board connectors. Compared with other connectors, board-to-board connectors do not require cables, and directly connect PCB boards together through pins, making the transmission links of power, signals and data easier. The design is shorter and the design is more compact, so it plays an irreplaceable role in low power consumption, signal integrity, and miniaturized design. At the same time, board-to-board connectors are also of great benefit to realize function expansion, improve design flexibility, and optimize system cost.

All in all, the board-to-board connector can make the connection between different PCBs more “as you want” in a limited space, so as to avoid the embarrassing problem that the PCB is difficult to “place”.

Phoenix Contact’s FINEPITCH series products are an excellent board-to-board connector series. The 0.8mm and 1.27mm pitch products in this series have a data transmission rate of up to 16Gbps, a rated test voltage of 500VAC, and an operating temperature range of -55°C to +125°C, enabling signal and data transmission in a small space. Ideal for industrial PCB connections.

PCB nowhere to “place”? A few industrial PCB interconnection skill points, help you solve it!

Figure 1: FINEPITCH series board-to-board connectors

(Source: Phoenix Contact)

The reason why FINEPITCH series board-to-board connectors perform well is due to the ScaleX double-sided contact system used in the 0.8mm version. This technology plays a key role in achieving stable and flexible PCB connections.

Figure 2: ScaleX double-sided contact system

(Source: Phoenix Contact)

First of all, ScaleX technology adopts the design of internal and external double contacts, which can realize both female and pin connections, and has good anti-vibration performance even in a compact space, ensuring a stable and reliable connection.

Secondly, the ScaleX contact system also has a very good “fault tolerance” design – the tolerance compensation function it provides allows a center offset of ±0.7mm and a tilt deviation of 2°/4° during mating, which can effectively Prevents damage to contacts inside the housing due to mismating, making the connector more robust and durable.

Figure 3: Excellent tolerance compensation function of ScaleX technology

(Source: Phoenix Contact)

In addition, the ScaleX contact system has two connection methods of pin type and socket type, which can realize different stacking heights – the stacking height of the 0.8mm series is from 6mm to 12mm (it will be expanded to 20mm in the future), and the stacking height of the 1.27mm series is from 8mm to 12mm. 13.8mm, providing users with more product options. At the same time, the pin connector can be fully inserted into the female connector when mating, leaving only the minimum PCB board spacing; and if you want to increase the board spacing, the pin connector can expose up to 1.5mm outside the contact area, and keep it A reliable contact area of ​​at least 0.9mm is left, which enables it to provide sufficient interconnection flexibility when product design or application scenarios change.

Figure 4: ScaleX technology’s scalable stack height enables greater flexibility

(Source: Phoenix Contact)

On the basis of the above-mentioned common advantages and characteristics, the two sub-series products of FINEPITCH series connectors, 0.8mm and 1.27mm, also have their own characteristics to meet the requirements of specific target applications.

A major feature of the 0.8mm pitch FINEPITCH connector is that it can provide excellent EMC shielding performance. In the design of the shielded connector, there are many shielding transition points between the female connector and the pin connector, which can quickly release the interference current, and at the same time, a good soldering process ensures a stable connection with the PCB, and the two If both external contacts are connected to ground simultaneously, excellent shielding can be achieved to prevent signal interference.

Figure 5: 0.8mm FINEPITCH connector has excellent EMC shielding performance

(Source: Phoenix Contact)

One of the outstanding features of the 1.27mm series products is that they can realize a variety of connection methods, including mezzanine connection, coplanar connection, mother board and daughter card connection, and wire-to-board connection using flat cables, which makes it adaptable to diverse Interconnection requirements make the connection of PCB more flexible.

Figure 6: The 1.27mm FINEPITCH connector enables a variety of connections

(Source: Phoenix Contact)

It can be seen that board-to-board connectors such as the FINEPITCH series combine the reliability, durability and flexibility of PCB connections, and can help developers properly “place” different PCBs in a limited space. Such a solution would naturally be popular in a wide range of industrial applications.

Modular Housing System

In people’s traditional cognition, the main function of the housing of an electronic device is to protect the internal PCB and components from the external environment, and at the same time prevent personnel from electrical damage. In fact, in addition to the protection function, the housing of electronic equipment also has the function of interconnection, which is the interface between the internal circuit or module of the housing and the external system.

In a complex control system (such as PLC), how to perfectly “integrate” the PCB with other components in the system through the housing instead of becoming “out of place” is a subject that tests the system-level design ability of engineers. . Facing this challenge, the technical path chosen by Phoenix Contact solution is standardization and modularization.

As we all know, in the design of industrial systems, DIN rails are widely used and become an industry standard because they provide a convenient installation method for electrical components. On the guide rail, the whole assembly process is very simple. As a result, Phoenix Contact produced a housing design idea:

Develop a housing that conforms to the DIN rail standard, so that the PCB and electronic modules can be neatly “placed” on the DIN rail like other electrical components, and can be connected with other external functional modules in an orderly manner; at the same time , on the basis of this standardized design, and then through the modular design, a multifunctional and serialized shell product is formed to meet the needs of continuously expanding applications.

According to this design idea, Phoenix Contact has created the ME-IO series of multifunctional electronic module housings.

Figure 7: ME-IO series multifunctional electronic module housing

(Source: Phoenix Contact)

Advantageous features of the ME-IO housing system include:

1. It adopts front wiring and supports front in-line connection, which can easily realize on-site connection of signal, data and power lines.

2. The wiring density is high, the pitch is 3.45mm and 5.0mm, 4-position and 6-position connectors can be provided, and the total width of a single device of 18.8mm can realize up to 54 wiring positions.

3. Provide three module widths (18.8mm, 37.6mm and 75.2mm), suitable for various applications.

4. Easy to disassemble and assemble, using the lock-and-release system, which can quickly and easily lock and release the connector, and can quickly replace the module without special tools and time-consuming wiring work.

5. Connectors and sockets are equipped with a variety of anti-wrong coding components, which can improve the reliability of the plug-in interface.

6. Provide 8-position DIN rail bottom connector for easy inter-module communication.

7. With the help of the module fixing belt, any mechanical grouping of the connectors can be carried out in a limited space, which further simplifies the operation and improves the efficiency.

Imagine placing the PCB in the ME-IO series of modular shells in a limited space. It is easy to install, connect, take into account safety and beauty, and can continuously expand new shell modules to meet new design requirements. This can undoubtedly elevate industrial PCB interconnection design to a new level!

Summary of this article

When hardware engineers expand their vision from PCB board-level design to system-level design of the entire product or solution, they will find that the layout and placement of each PCB is an unavoidable hurdle. If you can’t make it through, there will be a phenomenon of “nowhere to place” the PCB.

On the surface, this seems to be a design “beautiful” problem, but it reflects the shortcomings of PCB interconnection design at a deeper level. To make up for this short board, board-to-board connectors and modular housing systems are good solutions. The relevant products and solutions provided by Phoenix Contact introduced in this article are a good example. After mastering these skill points, your system-level design level can also reach a new level!

Related Technical Resources

FINEPITCH 0.8mm and 1.27mm board-to-board connectors, learn more>>

ME-IO series multi-functional electronic module housing, learn more>>

Source: Mouser Electronics

The Links:   MG100J7CSAOA G101EVN01.3