Circuit board differ from traditional rigid PCBs
The brains behind everything from smartphones to computers, circuit boards perform a vital function: they allow electronic signals to flow. A basic circuit board consists of a substrate—typically made of fibreglass or other insulating materials—with thin, conductive pathways etched onto its surface. These pathways, often made of copper, serve as the highways for electrical signals to travel throughout a circuit and execute specific tasks. Various electronic components, like resistors and capacitors, are then soldered to the board, forming a network that processes and directs electric currents.
The first step in creating a circuit board is designing the schematic, a detailed representation of all the parts and their connections on the board. This can be done on graph paper or by using simulation programs such as MultiSim and Eagle CAD. Regardless of the software used, the end result should be a clear and easy-to-follow diagram of the entire circuit board. This is crucial to ensuring that the circuit board will work as intended once it’s been designed and assembled.
Once the schematic has been mapped out, it’s time to start etching the copper traces on the circuit board. A copper layer is etched on either one or both sides of the board to form an intricate network of lines that are the pathway for electric signals to flow. The tracing is patterned in a way that ensures the positive and negative points of the circuit are connected to each other so electricity can pass from one point to the next without interference or loss of energy.
How does Circuit board differ from traditional rigid PCBs
Pads, which are small areas of conductive material on the circuit board, are then added to the circuit to connect different components to the traces. These pads are typically circular or oval and have an opening for the legs of through-hole components to pass through them and be soldered to the opposite side of the board. Surface mount components (SMDs) don’t have legs that need to pass through the pads, so they are positioned directly on top of them.
Another critical aspect of circuit board layout is the design of vias, or holes in the copper traces that provide electrical connections between different layers of the circuit board. The size, shape and location of vias can affect the performance and manufacturability of the board. They must be large enough to accommodate the conductive material, yet small enough not to weaken the board or take up unnecessary space.
Once the circuit board has been etched and its components are placed, it’s ready for the assembly process. Rigid-flex PCBs must be fabricated with a coverlay, a laminate that protects the copper layers and enables the board to be bent and flexed during manufacturing. They also require special solder masks that prevent the copper from contacting unintended areas of the circuit board. Once the flex-rigid PCB is complete, it must be tested to ensure all components and connections are functioning properly. If the flex-rigid PCB fails to meet quality standards, it will need to be modified before it can be used in a product.
