There are several kinds of Printed Circuit Boards (PCB). They differ in terms of sizes and materials needed for them to be manufactured. A certain amount of preparation is needed before the actual PCB fabrication begins.
First, a diagram of the board should be made. In this diagram, the connections of parts are shown, as well as the different parts needed to be used. Each part in the diagram must have a designator in reference to the list to be made later on.
Second is to list the materials needed for the PCB. Any useful information for each part that is not shown in the diagram can be included here.
Third is selecting the parts to be used for PCB fabrication from what is called a data sheet which is provided by part manufacturers. From this, one can select parts with certain specifications, like dimensions. If a part has no data sheet, one can create one for the manufacturer.
Fourth, the board to be used is to be specified; details such as the type of board, its layers, and its dimensions must be made clear. A couple of choices for the type of board can be either fiberglass or phenolic.
The layers of the board can be a single-sided laminate (where components are mounted only on one side of the board), a double-sided laminate (where components can be mounted on either side), or a multi-layer laminate (which is able to route a more complex circuit and distribute power more effectively). The physical dimension of the board differs depending on its function, connections of its parts, and many other external factors.
Fifth is drawing the PCB layout either manually or by computer. For simple circuit boards, the manual procedure for drawing the layout may be quicker but for more complex ones, using computer software is recommended. There are several things to consider when doing this. First is the placement of components. Usually, it is best for these to be placed on top of the board. Proper spacing for each component should be observed as well. Directional orientation should only be either up and down or left and right. The holes that will be drilled for mounting the components should be indicated as well.
Next is the placement of power and ground traces, by avoiding a zigzagging chain from part to part as much as possible, one can have a solid trace. Last thing to consider is the placement of the signal traces. Keeping them as short and direct as possible is recommended. The size of the trace depends on the amount of current it is going to carry. A trace carrying a low current should be smaller than a trace carrying a higher current.
Next, after doing all the preparations, take a moment to check if all the components for the board are placed properly. Check the routing of every signal if there are missing ones or incorrectly wired ones. From the diagram to the layout, check the path for each trace one by one to ensure that the diagram and layout match.
The last thing to do is to draw a PCB fabrication scheme. In this drawing, it’s necessary to indicate the dimensions of holes to be drilled on the board, the labels for each hole, and its quantity. This drawing, in addition to the other data created, will be used by the manufacturer to make the PCB.
After doing all the preparations, one can now deliver the information to the manufacturer for them to start the PCB fabrication process. It may be a tedious task but careful planning and preparation can help anyone avoid crucial errors in manufacturing the PCB.