How Is Printed Circuit Board Assembly Different From Traditional Rigid PCBs?
Printed Circuit Board Assembly Different From Traditional Rigid PCBs
Printed circuit boards are the essential building blocks for a wide range of electronic devices. These circuits contain copper lines that connect components to complete a system. Often times, complex PCBs contain multiple layers of circuitry. These layers are separated by insulating layers that make it possible to design electronic circuits with more complex connections.
There are three main categories of printed circuit board assembly: rigid, flexible and a hybrid rigid-flex. Each type has its own fabrication methods, assembly considerations, quality control needs and cost trade-offs. It is important to understand the differences between these three types in order to select the best one for a given application.
Rigid PCBs are found in traditional products like computer motherboards, audio keyboards and solid-state drives. These circuits are designed with multiple copper layers and insulating layers. Multilayer rigid circuit boards are ideal for high-performance devices, while single-sided rigid circuits provide a great solution for low-cost applications.
How Is Printed Circuit Board Assembly Different From Traditional Rigid PCBs?
To create a rigid PCB, manufacturers use a special material called FR4. This flame-retardant epoxy provides excellent electrical insulation and heat resistance. Additionally, this material allows for the drilling of holes without causing substrate or copper trace damage. In addition, FR4 is compatible with lead-free materials. This combination makes it easier for assemblers to mount components and maintain a high level of performance.
During the fabrication process, copper is printed onto the laminate using a photographic method. After the copper is printed, it must be etched away with a strong acid solution. Once the etching process is complete, it is necessary to drill holes into the board for the placement of electronic components. These holes are known as vias and must be drilled with precise accuracy. A legend (also known as silkscreen) is also printed on the PCB to indicate component designators, switch settings, test points and other indicators helpful in assembling, testing, servicing, and using the device.
When designing a rigid-flex PCB, the designer must consider both the rigid and flexible sections of the board. During assembly, the flex section can be bent and folded to fit around components to make another direct connection. This aspect helps to reduce the number of connectors and cable assemblies required in the end product. It also allows the design to be smaller overall, which can save on manufacturing costs.
A rigid-flex PCB is an ideal choice for complex electronics that require both flexibility and rigidity. These circuits can be made with a single-sided or double-sided rigid section and a continuous conductive copper layer with a flexible polyimide layer. These circuits can also be grouped together for processing as a panel. In this way, the design can be duplicated n-times for more efficient production and assembly. Additionally, panelization can reduce the number of components and parts needed to be shipped. This can help to cut shipping costs and minimize the risk of damage during transit. Altest offers a free design for manufacturing check to review a client’s PCB designs, including part spacing, pin indications and footprint corroboration.