Report: The ruggedization of miniature connectors

The ruggedization of miniature connectors is a top design trend in the interconnect market, driven by the increasing demand for electronics in new vehicle platforms, according to a recent Molex report. However, the need for ruggedized and miniaturized interconnects is extending into other market segments, including consumer electronics, industrial automation, medical devices and smart agriculture.

(Source: Molex)

The report, “Breaking Boundaries: Uniting Ruggedization and Miniaturization in Connector Design,” looks at connector trends, industry requirements and design innovations. Molex defines “miniature connectors” as having a pitch of 2.54 mm or less, while “ruggedness” refers to features for withstanding the harshest environments and mechanical stresses.

Molex said the convergence of interconnect ruggedization and miniaturization has enabled major innovations in the automotive industry, especially in supporting electric vehicles and zonal architectures. It has also filtered into other industries and applications as enablers of key functionality for devices such as fitness trackers, smartwatches, smart-home devices, industrial robots, human-machine interfaces, endoscopes, insulin pumps and wearable health monitors.

They are also gaining traction in electric vertical-takeoff-and-landing aircraft, delivery and crop-monitoring drones, and vertical farming systems. To meet the requirements of these applications, smaller and rugged connectors must withstand extreme temperature and excessive vibration and shock, along with exposure to moisture, dust and corrosive chemicals.

As a result of this widespread adoption, Molex finds that engineers must not think of “rugged” and “miniaturized” as mutually exclusive. Durable and smaller connectors are needed to enable new devices and systems.

Meeting new requirements

In addition to general durability and reliability, these miniaturized connectors must also offer vibration and shock resistance, ingress protection, thermal resistance and corrosion resistance, as well as deliver high signal integrity and electrical performance. This leads to design and manufacturing challenges around material selection and processing, mechanical reliability, signal integrity and crosstalk, thermal management and manufacturing complexity.

For interconnect designers, this translates into a need for new designs, materials and manufacturing processes. Maintaining high signal integrity and electrical performance in compact, rugged miniaturized connectors is possible thanks to innovative contact designs, optimized signal routing and high-quality materials with strong conductivity properties, according to Molex.

“This ensures reliable data transmission, power delivery and overall functionality, even in challenging environments with high levels of electromagnetic interference or radio-frequency interference,” according to the report.

The report also finds that aluminum alloys and specialized, high-strength steel, as well as high-performance polymers, offer high durability and lightweight construction, but they also raise several challenges. Processing these materials into complex connector geometries often requires specialized techniques, including micro-molding, high-precision machining, laser welding or selective plating.

New miniaturization techniques are also needed, Molex said. One challenge is the need for high-precision manufacturing and assembly for connectors with dense pitch layouts, which can also raise the risk of crosstalk and ineffective heat dissipation.

Engineers use advanced signal routing techniques, shielding and isolation methods, and advanced thermal management strategies, such as heat sinks or thermal vias, to mitigate these challenges, Molex said.

Multi-functional terminals (MFTs) also deliver significant improvements in miniaturized connector designs, according to the report, by integrating multiple functionalities, including power, signal and even mechanical features, such as locking mechanisms, into a single, compact connector, reducing component count in new designs.

Molex expects connectors to integrate more functionality as MFT designs evolve.

The report also looks at top environmental factors that can compromise component reliability, and it provides strategies and solutions to ensure performance in harsh environments. These include features such as positive locking mechanisms, strain relief features and floating contact designs, as well as potting and encapsulation to meet vibration requirements.

For extreme temperatures, strategies include the use of high-temperature polymers, low-temperature and high-impact resistance materials, thermal management, and gold and palladium plating.

A few examples cited in the report are Molex’s DuraClik connectors that feature housings made from high-temperature PBT material and secure terminal retention to withstand extreme automotive environments; the Micro-Lock Plus Connectors with a positive locking mechanism and added strain relief; and Squba Connectors with IP68-rated seals certified as resistant to nearly five feet of water for 30 minutes.

What’s ahead in rugged, miniature connectors

Molex believes emerging trends will continue to push the boundaries of compact and reliable connectors. Some of these advancements include flexible electronics (FPCs and FFCs), nano-scale coatings, nanomaterials and 3D printing.

The microminiature connector market is expected to reach $2.9 billion by 2030, up from $1.8 billion in 2023, growing at a compound annual growth rate of 7.6%, according to Verified Market Reports. The report also finds that interconnect manufacturers are developing compact connectors without sacrificing functionality as a result of continued technology breakthroughs, with growth expanding in a variety of segments, including aircraft, consumer electronics, automotive and medical.