Newbies often confuse “PCB schematic” with “PCB design document” when talking about printed circuit boards, but they actually mean different things. Understanding the differences between them is the key to successful PCB manufacturing, so this article will break down the key differences between PCB schematics and PCB design for beginners to do this better.

Before getting into the differences between schematics and design, it’s important to know, what is a PCB? Inside electronic equipment, there are printed circuit boards, also known as printed circuit boards. The green circuit board, made of precious metal, connects all the electrical components of the device and enables it to function properly. Electronics will not work without PCBS.

PCB schematic diagram and PCB design

The PCB schematic is a simple two-dimensional circuit design that shows the functionality and connectivity between different components. PCB design is three-dimensional layout, in order to ensure the normal operation of the circuit after marking the location of components.

Therefore, PCB schematic is the first part of the design of printed circuit board. This is a graphical representation, whether written or data, that uses agreed symbols to describe circuit connections. It also hints at the components to be used and how they are wired.

As the name implies, a PCB schematic is a plan, a blueprint. It does not specify where the components will be placed. Instead, the schematic Outlines how the PCB will eventually achieve connectivity and forms a key part of the planning process.

Once the blueprints are complete, the PCB design comes next. Design is the layout or physical representation of the PCB schematic, including copper wiring and hole layout. The PCB design shows the location of the components and their connection to the copper.

PCB design is a performance-related phase. Engineers built real components on top of PCB designs, allowing them to test whether the equipment worked properly. As mentioned earlier, anyone should be able to understand the PCB schematic, but it’s not easy to understand its functionality by looking at the prototype.

Both phases are complete, and once you are satisfied with the PCB’s performance, you need to implement them through the manufacturer.

PCB schematic elements

Now that we understand the differences between the two, let’s take a closer look at the elements of the PCB schematic. As we mentioned, all connections are visible, but there are a few caveats to keep in mind:

In order to see the connections clearly, they are not created to scale; In PCB design, they can be very close to each other

Some connections may cross each other, which is practically impossible

Some connections may be on opposite sides of the layout, with markers indicating that they are linked

This PCB “blueprint” can be a page, two pages, or even several pages describing everything that needs to be included in the design

One final point to note is that more complex schematics can be grouped by function to improve readability. Arranging connections in this way does not occur at the next stage, and the schematic usually does not match the final design of the 3D model.

PCB Design Elements

Now it’s time to take a closer look at the elements of the PCB design document. At this stage we move from written blueprints to physical representations constructed using laminate or ceramic materials. Flexible PCBS are used for more complex applications where extra compact space is required.

The content of the PCB design document follows the blueprint laid down by the schematic process, but, as mentioned earlier, the two look very different. We’ve already discussed PCB schematics, but what differences can be observed in the design document?

When we talk about a PCB design document, we are talking about a 3D model that includes the printed circuit board and the design document. They can be single or multi-layered, although two layers are the most common. We can observe some differences between PCB schematics and PCB design documents:

All components are correctly sized and positioned

If two points should not be connected, they must be circuited or switched to another PCB layer to avoid crossing each other on the same layer

In addition, as we briefly discussed, PCB design is more concerned with actual performance, as this is to some extent the verification phase of the final product. At this point, the practicality of the actual work of the design must come into play, and the physical requirements of the printed circuit board must be considered. Some of these include:

How is the spacing of the components allowed for adequate heat distribution

There are connectors around the edges

In terms of current and heat, how thick must the various traces be

Because physical limitations and requirements mean that PCB design documents often look very different from the design on the schematic, design documents include silkscreen printing layers. The screen printing layer indicates letters, numbers and symbols to help engineers assemble and use the board.

It is required that all components work as planned after being assembled onto the printed circuit board. If not, it needs to be redrawn.

conclusion

Although PCB schematics and PCB design documents are often confused, actually making PCB schematics and PCB design refer to two separate processes when creating a printed board. PCB design, which is an important part of PCB performance and integrity, must be made prior to the creation of a PCB schematic diagram that can draw the process flow.