With the integration of high-performance vehicle technology into various types of vehicles in the transportation sector and the transition to electric vehicles, traditional decentralized electrical system architectures are reaching their limits. The complexity and high-speed characteristics required for advanced information entertainment, security systems, autonomous driving, and vehicle to infrastructure communication networks require new design strategies and connectors to address these challenges.
Vehicle Electrical System: Distributed, Domain, and Regional Architecture
The traditional decentralized vehicle architecture consists of up to 100 control units, each assigned a defined function, such as controlling the engine control unit (ECU), airbags, etc ABS/ESP, Seat adjustment system or climate control. Each controller works autonomously and communicates with other control units through a gateway. With the addition or improvement of vehicle functions, a control unit will be added for each new feature. In recent years, there have been significant changes in all types of vehicles, from van fleets to buses and then to cars. The increase in the number of functions has greatly increased the wiring and interconnection content of each vehicle.
The control units in the domain architecture are divided into different functional areas, each responsible for a specific area of the vehicle, such as the powertrain system, infotainment system, or safety functions. An independent high-performance computer (HPC) performs the primary control of the domain and coordinates the control units within its domain. For example, the security domain is responsible for supervising the control units of driver assistance systems, ABS/ESP, and steering systems. Domain architecture reduces the number of control units and, compared to traditional decentralized architecture, reduces the required wiring and installation work, effectively reducing weight and cost. Additional features can be easily integrated into upgrades or new designs.
In regional architecture, construction is not based on domains, but on local regions. For example, multiple functions are bundled in one area inside the vehicle. The functions of transmission system and information entertainment system can be combined and processed in one regional controller. The central HPC performs primary control of various regional controllers, reducing the number of control units and the resulting wiring by 50%.
High reliability and performance requirements
HPC and its corresponding interconnect modules must be designed according to the highest performance requirements. For example, processing imaging and sensor data in autonomous driving safety systems requires safe high-speed data transmission rates and shorter latency times. At the same time, signal transmission must not fail under any circumstances. High performance, speed, and especially reliable data transmission rates - sometimes in harsh environmental conditions - are the requirements for connectors in these systems.
The "readability" of a signal can be illustrated by an eye diagram, which shows whether the transmitted signal in the receiver can be uniquely assigned to the digital state 1 or 0. For this purpose, the signal is recorded, superimposed, and displayed using an oscilloscope through a defined transmission path. In this way, signal routes can be mapped to overlap. According to theory, the transition of logical states is infinitely steep, and signal lines are completely superimposed. The external interference factors and internal damage of the signal pair cause the signal to rise and flatten, while the amplitude level changes.
Electromagnetic influence can endanger the transmission of high-speed signals. Connectors, especially in high-performance vehicle applications, are exposed to extreme environmental conditions such as vibration and impact. The connector must be particularly sturdy to ensure uninterrupted signal transmission even in harsh environments. In this case, the main decisive factors are contact design, contact system, and termination technology.
Multi contact design ensures reliability in harsh environments
The traditional two-piece connector has one male contact and one female contact. However, under strong impact, the male connector may detach from the female connector. To prevent such contact interruptions, a double-sided female connector can be used to provide redundancy and improve contact reliability, as the second female contact ensures that the signal is always transmitted through at least one contact
Connectors using a 'gender neutral' terminal system are more robust. The special feature here is that the geometric shape of the contacts between the connector and the plug and socket is the same. Therefore, both have both female and male touchpoints. Therefore, each pin is contacted by two female contacts, and the plug and socket are interlocked and cannot be lifted up from each other. The double-sided female connector always ensures at least one contact when subjected to mechanical loads, while the interlocking geometry in the neutral contact system ensures that signal transmission always occurs through two contacts. Therefore, this high degree of redundancy achieves maximum contact reliability
It is precisely because of this shift towards centralized data processing through HPC that their role has become increasingly important. The reliability of signal transmission has never been more important than it is now.
