Today's and tomorrow's feature-rich, highly automated vehicles require a large number of inputs and outputs - for every sensor, actuator, peripheral, and display - and they all need their own cables, connectors, and harnesses. OEMs continues to add features that bring more input and output, such as radar, cameras, infotainment screens, and temperature sensors. But space for cable and circuit board terminals inside the car is always limited.

TE Miniaturized hybrid standard wireline to board connector

At the same time, with the continuous development of automotive electronic and electrical architecture, "Domain" is constantly playing an increasingly important role. As a set of regional functions, each domain is controlled by the domain controller in a unified manner, which requires the connection between the domain controller and the vehicle central gateway with high integration, high reliability and high stability. With the increasing number of functional units of the vehicle body, it also leads to the dense connection of the regional controller, and the layout of the domain architecture is increasingly flexible, which also poses more challenges to the connection requirements of the domain controller.

While wireless connections are common in consumer devices, in the automotive sector they are limited to niche applications. Despite limited space, dedicated cables and connectors are still the most cost-effective way to support the functions required by the vast majority of devices.

One way to solve this conundrum is to miniaturize the connector and shrink the wire gauge to achieve higher density. Connector sizes are trending toward 0.50mm, down from 1.5mm in the 1980s when automotive electronics began to gain momentum. Connectors of this size can accommodate cables from 0.35mm2 to 0.13mm2 and maintain high performance of electrical signals. Tiny connectors can be used for almost anything that needs a signal, from cameras that require high bandwidth to turn indicators that require very little bandwidth. Even low-power connections can be miniaturized to some extent, as long as the meter can maintain the required current.

Enter automation

Miniaturized connectors pose a number of challenges in the automotive field, the biggest of which is that they are too small for people to assemble. Achieving such precision requires capital investment in the automation equipment needed to cut, peel and crimp a large number of cables. Automatic insertion of connectors during vehicle assembly may also be necessary.

Automated assembly of small connectors from Ambof

To ensure that automation equipment can effectively handle small connectors, it is necessary to carefully craft connectors and cables so that they work well with automation equipment. For example, twisted pair is oval, not round, so it must be positioned correctly in order to be peeled and trimmed on the shield. The automated system also needs optical detection capabilities so it can see how the oval is oriented, or some kind of mechanical stop in the shield is needed to signal the correct orientation to the system.

Building cabling and connectors so that they work well with automation and with each other is critical to the successful use of miniaturization. Cable design must work with connector design, and design teams must work in lockstep with manufacturing teams, combining product development with process development so that automation technology is taken into account when creating new products.

Future 

Another challenge with miniaturization is that small connectors are too fragile, so connector designers have to think about what to do with the parts and how to protect them from harm before final assembly. For example, if the terminal of a miniature male connector protrudes 12mm, it does not require much force to bend the terminal. In this case, a retractable male terminal stabilizer may be required. The plate protection terminal of the stabilizer will slip out when the male connector is fitted with the female connector.

Other industries, such as IT and telecommunications, have pioneered the use of miniature connectors, and in fact, they have achieved even smaller terminals with a size of 0.40mm. As the demand for denser connections continues to increase, the automotive industry is likely to look further into this smaller size.