What role do flexible circuits play in automotive applications?
What role do flexible circuits play
In order to enable next-generation automotive innovation, a variety of innovative electronic features need to be integrated into the vehicle. These features include curved display panels, flexible LED lighting systems, electronic control modules and sensors. These features are enabling automotive manufacturers to deliver innovative and technologically advanced vehicles. Flexible circuits play an essential role in this trend by enhancing design flexibility, simplifying installation and optimizing electronic performance.
A flex circuit is made up of several layers. These layers may contain copper traces, adhesives, laminates and polyimide materials. The number of layers will determine the total thickness and stiffness of a flex circuit. It also depends on the number of interconnections, shielding requirements and the overall size required.
The main advantage of a flexible circuit is that it can be bent or folded without any loss in strength or electrical performance. This enables the circuit to be fitted into tight spaces where traditional wire harnesses cannot. This allows for more space utilisation, simplifies modular assembly and interconnection as well as reducing vibrations and lowering weight.
What role do flexible circuits play in automotive applications?
In addition to the space and weight benefits of a flex circuit, it is extremely reliable. It is able to resist high temperatures, harsh chemicals and a range of atmospheric conditions. It can also withstand continuous vibrations and mechanical stress. This makes it an ideal replacement for standard interconnection techniques in the automotive industry such as soldered wires or hand-wired connections.
There are a variety of different types of flex circuits available depending on the application and requirement. One type, known as single-sided flex, has a conductor layer on a flexible dielectric film with a single access hole through which component leads can be passed for connection. It can be fabricated with or without a protective coating.
Another type of flex circuit, called double access flex, has a conductor layer that is accessible from both sides. This type can be fabricated with or without a coating and offers the advantage of being more cost-effective than single-sided flex, although it requires more processing.
Multilayer flex circuits are more expensive than single-sided and double-access flex, but offer a great deal of design flexibility and can be used to meet specific requirements for shielding or high component density. They can also be used to achieve a higher degree of thermal resistance and/or vibration isolation.
The automotive instrument cluster market was the original volume driver of flex circuits and is still a critical segment for this technology. In this market, flex circuits are used to deliver power and connectivity to instruments mounted on the vehicle dashboard. These include lighting, power, sensor connections and touch buttons.
In this case, the flex circuits are designed to be installed in an area that will be subjected to frequent flexing. These flex circuits must be able to withstand billions of flexing operations, without failure or degradation. Pyralux was originally selected as the flex circuit material for this application. It is capable of handling these demands and has been in use in millions of cars for over 20 years. It has been tested under actual operating conditions on multiple gearbox systems and car platforms, with no field failures due to material failure.