Rigid Flex Circuits on Electronic Packaging
Rigid flex circuits are becoming increasingly popular in a range of products, from laptops and digital cameras to medical devices. These unique printed circuit boards offer the best of both worlds—combining rigid and flexible components to improve functionality in a compact form factor. When used correctly, rigid-flex PCBs can be an ideal solution for high-impact and high-complexity applications that require space-saving solutions.
One of the primary benefits of using rigid flex circuits is that they can reduce or eliminate the need for wired connections between circuit boards. This saves time and money during assembly, and it also helps to minimize risk within the supply chain. A rigid-flex PCB’s flex area materials take up on average only 10% of the total board space, and they have tighter bend capabilities that can accommodate a greater number of interconnects than a wired solution.
The design of rigid-flex circuits is important, as it can affect both their electrical and mechanical performance. The layer stackup and material choice can have a significant impact on the PCB’s ability to handle signal integrity, power requirements, and thermal management. The use of a polyimide ribbon, for example, makes it easier to ground and extend power and signal paths between rigid boards, which can help to prevent EMI interference in the final product.
The Impact of Rigid Flex Circuits on Electronic Packaging
Aside from the obvious cost and design efficiency benefits, rigid-flex circuits also enable a reduction in overall product weight and size. Rigid-flex PCBs are more flexible than traditional rigid boards, allowing them to fit in spaces where multiple rigid boards and connectors would not be possible without a custom enclosure. Adding a flexible section can also improve the shock and vibration resistance of a device, enabling it to better withstand rough handling.
Lastly, rigid-flex PCBs have the potential to increase component density by eliminating the need for separate wired connections between rigid and flexible areas of the board. The plated through holes (PTH) and mounting components can be integrated into the flex section of the circuit, which eliminates the need for additional wired connections between rigid boards. This allows designers to build circuitry to fit their device, rather than vice versa.
However, it’s essential to work with a PCB fabrication partner that has a deep understanding of rigid-flex technology and is able to provide detailed design assistance to ensure the best results. For this reason, it’s a good idea to include your fabricator in the design process from the beginning of the project. By doing this, you can avoid many costly errors that could be introduced by a poorly-planned flexible section. For example, if your flexible section isn’t properly reinforced with the correct thicknesses and materials, it can be susceptible to stress and failure over time. By working with a trusted fabricator, you can be confident that your rigid-flex PCBs will be mechanically reliable and durable for the life of the final product.
