A press-fit connection refers to the fastening of two automotive parts into a printed circuit board (PCB) without using solder joints. It comprises two types of pins that are pressed into the PCB. These include the compliant pin that consist of an elastic press-in zone and the solid pin that comes with a solid press-in zone.
In this post, we discuss everything you need to know about press-fit technology, with a special focus on elastic press-in zones.
Press-fit technology is fast becoming an integral part of PCB design and it is applied in a wide range of engineering and automotive applications. With that said, there are two options customers need to consider as far as press-fit technology is concerned.
The first option is press-fit contact terminals that are normally used for single-pin insertion while the second option is connector modules that come in handy for mass termination.
Press-fit contact terminals come in a reeled condition. This allows customers to apply the terminals to the printed circuit board in a flexible manner. Conversely, connector modules for mass termination come with customized housing components. They consist of contacts and other components that are supplied in a modular way in line with the specific needs and preferences of the customer.
Press-fit Technology Market Trends
The current market trends spurring product development for the automotive industry include:
Increase in Electronic Systems
The past decade has seen a significant increase in electronic content. Today’s vehicles use a high number of electronics to operate and perform various functions. From intelligent bus systems to AI distribution boxes, these systems have replaced simple cable connections and ignitions. All these electronic advancements are intended to enhance safety, comfort, and performance, but they require the right electrical connections to achieve these objectives.
Demanding Environmental Conditions
Many manufacturers prefer press-fit connections to other electrical interconnections since they are more reliable and can withstand harsh environments. Press-fit contacts do not use solders and they eliminate the risk of dry joints. Moreover, they are designed to meet the demands for increased functional performance, further guaranteeing improved quality and dependability.
Thinner PCB Designs
PCB designs are becoming thinner every day. While the current PCB boards are about 1.6mm thick, it is just a matter of time before they go down to even 0.8mm. Modern automotive applications require thinner PCBs that are less than 1.2mm or 1.0mm thick. This calls for press-fit solutions that fit into these new PCB designs.
Miniaturization in the automotive industry has become inevitable as most customers are demanding smaller, safer, and more affordable vehicles. These smaller vehicles use electrical control units (ECUs) to control various functions and applications. The ECUs must be as compact as possible to deliver the desired performance. Each ECU has a PCB that completes the electrical interconnections between components, and this drives the development of press-fit solutions.
Press-fit vs Soldering – Which is better?
Gone are the days when lead was the standard material for soldering. Nowadays, manufacturers use plastic materials like PCT, LCP, PPA, and PPS during the soldering process. However, these materials are relatively expensive and they require a higher temperature for an efficient soldering process.
To avoid the increased costs, press-fit technology is the most viable alternative. After all, it does not require any expensive high-temperature materials. In addition, press-fit technology is an ideal solution for miniaturized PCB designs that cannot be realized through traditional soldering processes.
Larger soldering headers may interrupt the surface-mounting reflow process, thus making it difficult to complete a connection. The header temperature can drop too low leading to a faulty soldering process. This is where press-fit technology comes into the picture. Customers can use press-fit technology for big connectors in conjunction with a reflow soldering process. You only need to add the header using press-fit technology after the soldering process is complete.
Another highlight of press-fit technology is that it is a fast and inexpensive manufacturing process. Its fit rate of 0.006 makes it one of the most reliable connection techniques. Moreover, press-fit technology allows for the repair of the press-fit pin-up to two times.
Tips on How to Use Press-fit Technology
Press-fit technology is ideal for various engineering and automotive applications. One of the most common methods of using press-fit is as a standalone pin that is inserted into the PCB. The contact terminal of the standalone pin comes with a shoulder geometry that provides adequate support to press the pin into the printed circuit board. Insertion rates of five pins per second can be achieved for standalone 5mm pins.
Another method of using press-fit technology is as a press-fit pin header that consists of contact terminals in a plastic housing. The pins are stitched together or assembled using an over-molding process before they are inserted into the PCB by pressing the shoulders of the pin. The pin header assembly can be manual, semi-automatic, or automatic depending on the annual numbers needed.
Press-fit technology can be used in an integrated module or housing, and examples include actuators, coils, capacitors, and sensors. These elements share a single PCB design in the same housing or module.
Benefits of Press-fit Technology
The advantages of using press-fit technology over conventional soldering are almost endless. Here are the top benefits of press-fit technology:
- Fast and reliable process
- Eliminates the risk of cracking and dry joints
- Prevents solder formation problems
- Uses affordable resins instead of expensive high-temperature materials
- Allows for standalone pin insertion
- Lubrication-free process
- Flexible application design with programmable pin arrays
- Ability to withstand thermal expansion
- Delivers consistent results through automated press-fit assembly processes
Press-fit technology is the perfect match for all types of contact to PCB design connections. Try it today and notice the difference.