Everything You Need to Know About Circuit Card Assembly

Circuit cards have enabled the creation of more compact, efficient, and powerful devices, from advanced avionics and satellite systems to smartphones and wearable technology. However, the circuit cards themselves are made through a method called Circuit Card Assembly (CCA). In this blog, we will break down how bare boards are transformed into fully operational electronic assemblies through the CCA process, from design through testing.

What Is a Circuit Card?

A circuit card is a flat board made of insulating substrate material with etched copper traces. These traces form the conductive pathways of an electrical circuit, acting as highways for interconnecting various components and forming functional systems.

Use Cases

• Aerospace and defense flight control systems, as well as radar, communications, and surveillance equipment
• Consumer electronics like smartphones, tablets, and wearable tech that rely heavily on compact circuit designs
• Medical instrumentation
• Automotive infotainment and safety systems
• Industrial control and automation equipment

The Circuit Card Assembly Process

Step 1: Designing the Circuit Card

Engineers use Computer-Aided Design (CAD) software to map out the electrical layout, determining trace paths, power distribution, ground planes, and the optimal placement of all components for electrical performance and space efficiency.

Step 2: Converting Design into Manufacturing Instructions

The CAD file is imported into a Computer-Aided Manufacturing (CAM) system, which generates the files and instructions needed for the automated assembly process.

Step 3: Etching the Circuit Traces

A photolithographic and chemical etching process is carried out to define the copper traces on the board’s surface, with unwanted copper being removed to create the desired circuit pattern.

Step 4: Component Placement

Once the traces are formed, electronic components such as resistors, capacitors, and ICs are positioned on the board, usually handled by pick-and-place machines to be as accurate in their orientation and alignment as possible.

Step 5: Soldering

The placed components are soldered to the board to establish strong and conductive joints. The chosen soldering method depends on the component type and board design:

• Reflow Soldering: Ideal for surface-mount technology (SMT), as well as high-density and multilayer designs, this method starts with solder paste being applied to the pads before components are placed. After placement, the board is passed through a reflow oven where controlled heat melts the paste and solidifies the connections.
• Wave Soldering: Suited for through-hole components or mixed-technology boards, in wave soldering, the entire board is passed over a wave of molten solder that bonds component leads to the pads. This approach is faster and more cost-effective for assemblies with fewer SMT components.

Step 6: Post-Assembly Testing

Finally, the board is typically cleaned to remove flux residues. It then undergoes visual inspection, automated optical inspection (AOI), and in many cases, in-circuit testing (ICT) or functional testing to validate performance and compliance with quality standards.

The Advantages and Disadvantages of Circuit Card Assembly

Advantages

• Multilayer layouts and advanced materials allow for dense routing and support more complex systems.
• More components can be placed in a smaller area.
• Especially in mid- to high-volume production, automated CCA reduces labor costs and increases throughput.

Disadvantages

• High component density, miniaturization, and the automated construction process can make diagnostics and manual reworks more challenging.
• While ideal for mass production, the initial setup can be time-consuming for small production runs or when creating prototypes, especially in regards to programming pick-and-place machines.

Simplify Circuit Card Assembly Sourcing with Just NSN Parts

Circuit card assembly makes the production of high-performance, space-efficient electronic devices possible. With circuit card assemblies being carefully designed and often subject to strict quality and compliance standards, partnering with a trusted procurement platform ensures you receive authentic, traceable options that will readily meet the demands of your project. More than that, sourcing from reputable suppliers helps mitigate risks like component failure, delays in maintenance schedules, or non-compliance with regulatory frameworks.

At Just NSN Parts, an ASAP Semiconductor website, we present a curated selection of circuit card assemblies, electronic components, and more products that are all sourced from vetted global manufacturers. Meanwhile, our robust search tools, curated catalogs, and dedicated support team simplify the process of tracking down exact parts of need. To see how we can save you time and money in your procurement endeavors, connect with one of our representatives at your convenience.