In a way, we answered the question “what is a printed circuit board?” in Unit 1: a PCB is a product that mechanically supports electronic components and allows them to be connected together on the same surface. While this sentence is true, there is much more going on inside of a PCB than the components and copper connections you see on the surface.

Before you can become a PCB designer, it is important to understand what goes on inside of a PCB. All PCBs have similar structures that are used to mount components and allow them to be connected electrically. The structure of modern PCBs did not happen by accident, it has slowly developed alongside PCB manufacturing capabilities and processes adopted by the electronics industry.

PCBs need to be designed so that they can be easily fabricated and assembled, something that is sometimes more difficult than it sounds.

Today, designers focus on a practice called design for manufacturing, or DFM, the goal of which is to ensure a bare board is designed so that it can successfully pass through the PCB fabrication and PCB assembly processes. PCB design software is also developed with the goal of ensuring a designer can implement DFM practices in their PCB layout and so that the structure of a fabricated circuit board is consistent with the requirements of the PCB manufacturing process.