Rigid Flex Circuit Boards

Rigid flex circuit boards combine rigid PCB elements with flexible sections for a hybrid solution. The combination of rigid and flexible PCBs allows for design versatility, a more streamlined assembly, improved high-speed signal performance, and better shielding to protect against electromagnetic interference (EMI). These characteristics can make rigid flex circuit boards ideal for use in electronic devices that require both rigidity and bending/flexing, such as flip-style cell phones or laptop computers.

The rigid section of a rigid flex circuit board carries the components and the flex sections are used for interconnecting the components. The conductive layers are typically made of copper, with different trace widths and spacing to accommodate the various flexing areas of the circuit board. The flex sections also have copper-plated through holes (PTHs). These holes allow for electrical connections to be made across the layers.

A single-sided rigid flex circuit has two conductive layers on either side of the polyimide base layer. The traces are then copper-plated with specific patterns to create the desired circuit layout. These patterns are etched on the rigid sections to create the necessary paths of conductors. The plated through holes (PTHs) can be filled with solder for final connections.

Can Rigid Flex Circuit Boards Be Recycled?

There are two main functional applications for a rigid flex: Static and Dynamic. Static applications only need the flex to flex when being installed, whereas dynamic flexing will occur throughout the lifetime of the product. A double-sided rigid flex can be manufactured with a wide range of copper foils, varying in thickness from Electro Deposited (ED) to Rolled Annealed (RA).

In addition to the flexibility that they provide, rigid flex circuit boards offer a number of advantages. For example, they can reduce component and connector costs by eliminating the need for wired interconnects. They can also help to improve system reliability by reducing mechanical stress and improving vibration resistance. Finally, they can simplify assembly by minimizing the number of connectors, which can improve manufacturing efficiency and speed up the overall assembly process.

With the increased functionality of a rigid-flex, it is important to consider how your circuits will be designed and manufactured. The choice of materials for both the rigid and flex sections will impact how the board performs, and you will want to ensure that the material properties are compatible. Different materials can have varying thermal expansion coefficients, which can impact the reliability of the circuit during temperature variations.

Rigid-flex circuits have the added advantage of being thinner and lighter than other types of PCBs, which means they can be incorporated into smaller and lighter products. They are also more rugged and durable than their fully flexible counterparts, making them suitable for more demanding environments. This makes them the preferred option for medical devices and consumer electronics that need to withstand harsh conditions. The durability of rigid flex circuits comes from their ability to resist mechanical stress and vibrations while still being able to dissipate heat effectively. For these reasons, it is essential to plan and test your circuit boards thoroughly before production begins.