Flex PCBs Are Used in Automotive Applications

The use of flex PCBs in automotive applications is gaining popularity thanks to the fact that they can conform to unique shapes and contours found in many different automotive electronics. They can also offer a number of advantages over traditional connectors, including reduced weight and more reliable connectivity. However, there are some important planning considerations that need to be taken into account when integrating these flexible circuit boards into automotive devices.

In addition to their ability to conform to the distinctive shape of automotive components, flex pcbs are known for their resistance to harsh environments. They can also be made to withstand high temperatures, making them a great choice for most automotive electrical systems. These factors have helped them to become a leading choice for many automotive manufacturers as they seek to reduce the size and weight of their electronic products.

flex pcbs are also able to offer a higher conductor density than traditional ribbon cables. This can be useful for reducing the number of external connectors on the finished product and thereby lowering its overall cost. Additionally, flex circuits can be interfaced with rigid boards without the relatively tall and bulky connectors that flat cables require, or, in the case of a rigid-flex construction, they can be integral with the board itself and eliminate the need for external connectors altogether.

How Flex PCBs Are Used in Automotive Applications

When designing a flex circuit, it is important to consider the layout and layer stack-up. Depending on the application, it may be necessary to include a rigid section in the design to provide stability. It is also possible to add what is known as stiffeners which are pieces of rigid material (usually FR4) added to specified areas of the flex circuit to increase its thickness and provide more mechanical strength.

One of the biggest drivers of flex circuit technology in the automotive industry has been the instrument cluster market. This is where flex PCBs are used to deliver power and connectivity to the different instruments on a vehicle’s dashboard. Another major driver is the growing demand for advanced technologies in vehicles, such as autonomous driving and electric vehicle functionality. These technologies will drive the need for more compact and efficient electronic systems that can be fitted within the limited space available in a motor vehicle.

The most common substrates for flex circuits are a mixture of PI and PET films and thin flexible epoxy-and-glass-fiber cores. In some cases, copper cladding is also used to enhance the electrical performance of a flex circuit. A protective polyimide or polyethylene naphthalate overlay is also often included to prevent damage from chemicals, solvents and other contaminants that can come in contact with the circuit.

When choosing the flex substrate/film type, it is important to choose one that offers a suitable CTE (coefficient of thermal expansion) for your particular application. It is also important to consider the design requirements for the flex circuit, particularly its bending capabilities. If the curve range is too small, it can lead to mechanical failure of the copper follows, and if it’s too large, it can cause arcing during flexing and twisting.