Interplex Junction - The Place to Connect

For over 50 years a variety of Press-Fit connectors have been widely used in the telecom and industrial markets. The technology available for those markets works well in most controlled environment applications where mobility, vibration and harsh environmental conditions are not encountered.

The ongoing development of electronic systems for use in such applications as automotive and transportation systems and green power applications requires the units to operate under quite aggressive conditions and severe ambient environments. Over recent years, there have been several significant design upgrades and changes to past press-fit designs that were needed to move the technology to support these harsher environments.

Driven by the explosive growth of automotive electrical systems and many other industries using inverter and converter based power modules, press-fit technologies have become the preferred alternative for delivering highly reliable, solderless interconnect solutions.

To support the growth and performance demands of new applications in the automotive, transportation, green energy and power module industries, solderless press-fit interconnects are being designed and tested to carry much higher current levels than was typically considered feasible in the past.

Maintaining sufficient retention force is absolutely critical for the long-term operational integrity of any
press-fit interconnection. Therefore press-fit zone designs must be tested to meet the application's
minimum retention force requirements and operating environments using IEC-60352-5 requirements
as a baseline guide.

Testing both before and after multi-axis environmental stress includes but is not limited to: thermal shock, high/low temperature exposure, vibration, climatic cycling, temperature and humidity cycling and other similar test requirements. In addition, to assure a wide process control window for assembly and to minimize deformation to the plated-through hole, it is important that press-fit zone designs conform to maximum insertion force parameters.

Press-fit technology has come a long way over recent years and has been adapted for use in a wide range of applications in diverse industry segments, including automotive, power modules, transportation, industrial equipment, communication systems, appliances, lighting, utilities, green energy, mobile devices, wearable electronics and many other consumer products.

Performance testing has confirmed that solder-free Press-fit pins satisfy stringent operational requirements, including qualification to high temperatures, vibration, shock, and have excellent thermal expansion (CTE) characteristics for improved performance over extended product lifecycles.

However, as with any significant design program, it is vital to consider all of the relevant factors up front in order to get the best results out of your press-fit investments.  No new journey should be undertaken without a road map.  That's why we've created the Press-Fit Applications Evaluation Checklist.

In addition to this overview checklist, you can drill down into detail on virtually any related topic by visiting the full library of Interplex Press-Fit Tech Bulletins.

The following three primary requirements must be addressed for verification of press-fit zone designs:

• Plated Through Hole integrity (cross-section analysis)
• Mechanical Forces (insertion & retention forces)
• Contact Resistance (electrical measurement)

Before considering the use of any press-fit zone design, it is critical to know that it has been through and has passed a comprehensive environmental test program based on IEC-60352-5 requirements.

Maintaining contact resistance within specified parameters is a critical performance factor for the success of any press-fit application. Therefore all press-fit zone designs must be tested to meet the specific application's contact resistance requirements within the targeted operating environments.

Driven by the explosive growth in electrification of automotive systems, commercial transporation, green-power initiatives and many other industries using inverter and converter based power modules, press-fit technologies have become the preferred alternative for delivering highly reliable, solderless interconnect solutions.

However, achieving applications success with compliant press-fit interconnects requires a thorough understanding of the issues that impact current carrying capacity as well as the knowledge base to assure that your supplier has conducted proper testing and certification of their interconnects.

The evolution of electronically controlled automotive features already encompasses a variety of functions such as GPS navigation systems, anti-lock brakes, vehicle stability control, hybrid drivetrains, and tire pressure monitors. 

This on-going transformation of automotive technology has now shifted into a higher gear with the development of autonomous driverless cars that include car-to-car communication, infrastructure information sharing, automatic parking and more.

The spread of these electronic capabilities and their importance for safety and core automotive functionality has raised the bar with regard to reliability of all elements that make up and interconnect the underlying systems.

Card-edge interconnects are critical for the success of a wide range of today's electronics assemblies, especially those involving mother-board to daughter-board or other PCB-to-PCB connection requirements.

Maximizing production efficiency typically requires that the mother-board be fully assembled and tested prior to integration of daughter-boards.  Also board assembly processes need to be optimized for high-automation, mixed-technology, SMT production, with secondary processes kept to a minimum.  Finally, it's important to not risk damage to components by reheating completed assemblies during secondary soldering steps.

The combination of SMT Card-edge connectors with solder-free compliant Press-Fit technology has moved to the forefront as the go-to solution for most PCB-to-PCB interconnect requirements.

Just as the PC/104 standard allows a wide range of choices for creating a variety of system-level configurations, designers of board-level solutions and sub-system modules also need to be aware of different choices about how best to implement the PC/104 connectors on their products.

One of the key opportunity areas for improving quality, cost and production efficiency is using either solderless or self-soldering interconnects - both for the PC/104 bus connectors and others, such as the I/O edge-mount connectors typically found on most PC/104 assemblies.

Let's face it.  Some things just naturally belong together.

Press-Fit/Compliant technology and insert molded plastic electronic modules are definitely one of those perfect matches that makes a lot of sense from the start and then just keeps getting better with time.