Most of the electronic devices we use every day use circuit boards. The base layer of a circuit board is often made of plastic or other material that does not conduct, or allow, electricity to flow through it. This is important because the circuit is built upon this base layer. Electricity will flow through the circuit but not through the base.
Several components, or parts, are attached to the board and connected to make a circuit. The components on the circuit board are often connected with copper wires that let the electricity flow from one component to another. The circuit board can control which of the components get power and in what order.
When a battery or other power source provides electricity to the board, it flows along the wires to each of the components on the circuit board.
A printed circuit board consists of “printed wires” attached to a sheet of insulator. The conductive “printed wires” are called “traces” or “tracks”. The insulator is called the substrate.
A few printed circuit boards are made by adding traces to the substrate. The vast majority are manufactured by plating a layer of copper over the entire substrate, sometimes on both sides then removing unwanted copper, leaving only the copper traces. Some PCBs have a trace layer inside the PCB
After the circuit board has been manufactured, components are attached to the traces by soldering.
The three most common methods used for the production of printed circuit board are
Companies like TFS PCBA make circuit boards entirely to order. You can order them to suit whatever specifications you need. But there is no need to make every PCB to a unique specification.
Think about an Oreo Cookie. There are two layers: The delicious cookie discs on the outside and the filling on the inside. Although not as tasty, a PCB functions similarly to our Oreo.
The first layer is made of plastic or a similar product that doesn’t conduct electricity. This is the base layer.
The next layer of the circuit board is usually a thin layer of copper foil. Copper is an excellent conductor of electricity. Some circuit boards have only one layer of copper. However, there can be as many as 16 layers or more in some very complex circuit boards.
In the pictures of the circuit boards shown in this lesson, did you notice the layer of green material? This green layer is called the soldermask (pronounced SOD-er). The soldermask acts like an insulator; it keeps certain components from touching the copper layer.