Introduction
The ability to design and manufacture printed circuit boards (PCBs) is critical for electronics makers, as it enables them to create compact and reliable electronic devices.
If you have tried to build your very own circuit without the assistance of a computer program, you know the struggle of not really knowing why the circuit doesn’t perform as calculated. Maybe there is just too much noise in the circuit or a loose connection somewhere. Who really knows? Also if you aren’t careful the circuit might even shock you if you're not looking! Just look at this sad circuit below.
So how do we exterminate these annoying factors from our circuit building process and at the same time make the circuit beautiful? We do that by using a PCB print!
PCB design
A PCB (Printed Circuit Board) print refers to the layout design of a printed circuit board that is used to connect electronic components together.
PCBs are typically made of insulating material (such as fiberglass or plastic) with conductive copper traces etched onto the surface. The copper traces are used to create electrical connections between the components mounted on the board.
The PCB print is a visual representation of the circuit board design, showing the placement of all components and the routing of the copper traces. When you have your finished PCB print, you can kinda connect your components in the circuit on it like legos! (Sometimes it might need a little drilling though). Take a at look how neat and nice a PCB can be.
PCB prints are an essential part of the PCB manufacturing process, as they serve as the blueprint for creating the physical board. Once a PCB print is finalized, it is used to create the actual circuit board through a process that involves etching away excess copper and drilling holes for components to be mounted.
This is the step where we go from the theoretical, which includes the math and simulations for our circuit, to the practical. We might have been doing all the math correctly and we might have drawn our circuits perfectly in our simulation program and tested for the correct voltages and currents, but doesn’t ensure that it will work perfectly when we then put the circuit together.
Actually there are quite a few things to take into consideration. Let’s go through some of them.
Component placement
The placement of components on the PCB print should be carefully considered to ensure that they are positioned correctly and spaced appropriately. Components that generate heat, such as microcontrollers or power regulators, should be placed in areas with good airflow to prevent overheating.
Trace routing
The routing of traces on the PCB print should be designed to minimize electrical noise and signal interference. Traces should be kept as short as possible and avoid crossing over each other to prevent crosstalk.
Power and ground planes
Power and ground planes should be incorporated into the PCB design to provide stable power delivery and reduce noise. The power and ground planes should be as close to the components as possible and connected to each other with multiple vias to ensure a low impedance path. What is impedance again? Check out [blog] to find out!
Signal integrity
The PCB design should take into account signal integrity to ensure that signals are not degraded as they pass through the board. Factors such as trace impedance, signal reflection, and termination should be considered.
PCB layer stack-up
The number of layers and the arrangement of the layers in the PCB stack-up can affect the performance of the board. The PCB stack-up should be designed to minimize electromagnetic interference (EMI) and to ensure that there is sufficient space for routing and component placement. Electromag-what? See this [blog] to learn about electromagnetism!
Design for manufacturability
The PCB design should be optimized for manufacturability, taking into account the capabilities and limitations of the PCB manufacturer. This includes factors such as board size, minimum trace width and spacing, drill sizes, and copper weights.