By Rigid Flexible and Rigid-Flex PCBs
A PCB acts as the “physical canvas” for designing electronic circuits, connecting components with a series of lines that carry current through nets, plated holes and internal layers. These circuits enable data and signals to be exchanged between different parts of a device, whether it’s a laptop computer, tablet, or wearable.
The physical structure of a circuit board consists of multiple layers that are laminated together under heat and pressure with copper foil to form a monolithic structure. This multilevel lamination also supports mechanical support and offers specific electrical properties like dielectric constant, temperature decomposition, arc resistance, and loss tangent that impact circuit performance.
pcb manufacturing is a multistep process that includes the preparation of the base material and copper layer, as well as the placement and soldering of components and connections. Depending on your design requirements, you can choose from rigid, flexible or hybrid circuit boards. Rigid flex and rigid-flex circuits offer the best of both worlds, providing durability and flexibility in a compact design that can fit into tight spaces.
What is the Difference Between Rigid Flexible and Rigid-Flex PCBs?
Rigid flex circuits can bend, crease or fold in ways that would be impossible for rigid boards to do, and they can excise the need for connector cables between separate rigid PCBs. This can simplify assembly and reduce costs.
In addition, these circuits are designed to withstand mechanical stress and vibrations that can damage rigid circuit boards. In fact, many critical industries rely on rigid-flex PCBs for their reliability and durability, including medical imaging equipment, military missile guidance systems, and aviation technology.
A rigid flex circuit board is typically made up of four rigid layers with two flexible sections that are separated by a core. This core is often made of adhesive-less Polyimide to minimize the risk of fracture. Manufacturers then fortify the rigid and flex sections with low flow prepreg and copper film, and then cover them with solder mask and coverlay layers.
Flex and rigid-flex circuits are often used for complex, high-density applications that can’t be accommodated by traditional rigid PCBs. These include industrial robotics, networking devices, and vehicles with infotainment and safety features.
As a result, they need to be robust and durable to withstand mechanical stress, vibrations, and temperature variations. In addition, they require more precise design to ensure that signal layers are properly transitioned between rigid and flex sections. Otherwise, misalignment can result in impedance mismatches and signal degradation.
As a result, it’s important to work with designers who understand the advantages of rigid-flex circuits and are experienced in their design and assembly. These professionals can help you select the best flex-rigid hybrid circuits for your application, and they can work alongside you to prepare your prototype for manufacturing and generate all required deliverables including Gerber files. Working with integrated MCAD and ECAD tools can also make it easier to define your bending region and ensure your flex-rigid hybrid PCB will be robust enough for your environment.