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Ethernet technology has a promising future in the automotive industry. Data rates ranging from 10Mbps to 10Gbps are being, or already have been, standardized. To reduce the amount of cabling, a technology known as Power over Data Line (PoDL) has been developed that enables the data and power to share the same pair of wires. This paper will discuss the connector requirements needed to ensure safe power transmission for these PoDL voltages, and demonstrate a design that meets these requirements.

Ethernet technology using a single unshielded twisted pair (UTP) is considered to have a promising future in the automotive industry. While 100Mbps transmission speeds can be achieved with standard connector platforms, 1Gbps requires specific design rules in order to ensure error free transmissions. This paper explains the specific challenges for high speed UTP solutions applied in automotive environments. Automotive relevant signal integrity (SI) and electromagnetic compatibility (EMC) connector limitations are also discussed in detail. Through simulations and testing, the connector design criteria and rules necessary for meeting all the electrical and mechanical requirements for such automotive applications are evaluated and shown. This is followed by the introduction of a modular and scalable MATEnet Ethernet connection system utilizing an optimized cable termination technology.

Aluminum wire is receiving increased attention for automotive applications due to the potential for cost and weight savings. Termination of aluminum wire is problematic due to the tenacious surface oxide on the strands. The oxide is an electrical insulator and is difficult to displace during termination. Consequently, many of the strands within a crimped wire bundle can be electrically isolated from the terminal, which can result in higher than expected crimp resistance, less stable crimp resistance, and the potential for excess heating of the termination. Prior solutions employed additives such as brass powder to puncture the oxide film and form a diffusion bond between strands, or features such as screens or serrations that increase wire deformation and displace the oxide mechanically to promote strand-strand bonding. Both solutions have drawbacks. Additives increase cost and process complexity and can serve as contaminants to adjacent processes.

For most data and telecom fiber optic applications the physical contact (PC) concept is preferred for all indoor and even some outdoor applications. But when these connectors are subjected to a harsh environment, the performance of standard PC connectors has proven unreliable in many applications due to their sensitivity to contamination. The subject for this paper is the design of a small form factor expanded beam (EB) fiber optic contact pair suited for operation in a challenging environment. The contacts conform to the dimensional envelope of MIL-PRF-29504/4/5D and employ a separable lens unit design which provides the option for field-installable terminations. The EB concept typically exhibits a higher loss than the PC connection, but preliminary results of the new design indicate that the size 16 termini pair using 1.25mm lenses and ferrules yields a very good loss performance.

In copper wire, real time crimp monitoring has traditionally been based on force measurement during the crimp cycle. The force attributed to molding the copper wire into the terminal is a significant portion of the total force needed to form the crimp. Therefore, any wire deviation from the norm is translated into a force pattern aberration that can be detected using basic signal pattern analysis. As the mobility industry is contemplating replacing copper with aluminum wire, in order to save on weight and material cost, the traditional force monitoring becomes ineffective in detecting wire faults in the crimp. The reason is that aluminum is softer than copper, and most of the force exerted during the crimp cycle is consumed by forming the copper terminal itself. The small force deviation due to an aluminum wire fault becomes much more difficult to detect. Therefore, a new technique is needed to monitor crimped aluminum wires.