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- January 12, 2023
- PCB knowledge
- (0)
- 07 mins
PCB schematic – a professional guide to design and layout
Planning a schematic for a custom PCB requires precision and attention to detail. After that, you can lay out the blueprint for your PCB design. In this guide, we share what you need to create a PCB schematic for the custom fabrication of printed circuit boards. Of course, both the layout and schematic are essential when handling electronics. But still, even with a suitable layout and schematics, it is crucial to know how to assemble the circuit.
Even though some individuals might prefer the DIY fabrication of PCBs, we wouldn’t endorse this option. The best way would be to use a credible manufacturer to assist with assembling printed circuit boards. Don’t worry about the cost being high, as professional PCB fabrication has become pocket-friendly. With a company like IBE, you don’t have to bypass your budget to get quality printed circuit boards.
What is PCB schematic?
A PCB schematic is a technical drawing showing the layout of the printed circuit board. It also displays the electrical connections flowing through the board. The entire design process depends on the correct schematics.
In case of any troubleshooting needs within the circuit, technicians and engineers can use schematics to devise a solution.
When you’re coming up with the PCB schematic, you must first consider what will be added to the board. Part of what will be added to the board includes passive components, capacitors, resistors, processors, and microcontrollers.
The purpose of the schematic is to show where all the components are found within the printed circuit board. In addition, it should also display the connections that lie between these components.
When working with complex circuits, it can become cumbersome for designers to visualize the connections and components. That’s why a PCB schematic is fundamental. It also makes it easier for troubleshooting, as an expert can see the flow and organization of various components.
How do you find the PCB schematic?
There are many ways to find a PCB schematic in an electronic device. Here are some of the most common ways you can use:
Reverse engineering
You can take apart the PCB and attempt to follow the physical layout as you create your schematic. However, there are better ways to find the PCB schematic, as this might not be easy for the average person.
Reaching out to the manufacturer
Yet another option you can use is contacting the manufacturer. They are in a better position to give you the PCB schematic.
Research
Carry out some research online using resources that can have the PCB schematic you’re looking for. Some possible resources to check include technical documentation websites and technological forums.
The manufacturer’s website
Though not all of them, some manufacturers add the PCB schematic on their websites. It can either be an image or a document that you can download.
Remember that some schematics may be subject to copyright and patent. Hence, they may never be available online or offline.
How to read a PCB schematic?
To comprehend and read a PCB schematic, here are some of the ways you can use:
Get familiar with the symbols
Symbols represent components on a PCB schematic. That is why you need to get familiar with these symbols for reference.
Comprehend the layout
Schematics are typically in grids. Every component has its spot within the grid. The spot a component holds on the schematic is the same spot it bears on the physical PCB.
Follow lines
Every component within the schematic is linked to another one using lines. The lines are a representation of the electrical connections within the circuitry. Follow the lines to see the interconnection of components.
Concentrate on the labels
Designators label the components found on a PCB schematic. These designators help in identifying the components. The labels are next to the component symbol and may include the function and value of the element.
Locate power and ground connections
They are indicated using specialized labels and symbols. Know how these connections come into action, as it helps with the optimum functioning of the circuit.
PCB schematic symbols
Symbols, as stated above, help to represent components used on a PCB. For example, some of the symbols in a PCB schematic include the following:
- Integrated circuits (IC) – represented by a rectangle with a dot in every corner.
- Transistor – represented by a rectangle with three lines coming out of it.
- Diode – represented using a triangle with a line through it.
- Inductor – represented using a series of loops.
- Capacitor – represented using two parallel lines separated by a gap.
- Resistor – represented using a zigzag line.
These are but some of the symbols you may find. Several other symbols can represent various components. Get familiar with as many symbols as possible so as not to get confused.
How to draw and design a PCB schematic?
The following steps are essential when drawing and designing a PCB schematic:
Step 1: Put tools together
A computer with a PCB design program is the first two things you need to put together. After that, CAD, KiCAD, or EAGLE are some of the software to pick. A schematic capture tool will also be necessary to create and edit the schematic.
Step 2: Identify the circuit’s function
What is the circuit’s purpose? Once you answer this question, you will know the components needed and how they will be connected.
Step 3: Select components
Choose components to use within the circuit. Consider the size, layout, functions, and requirements of the circuit.
Step 4: Place components
Arrange the components on the schematic to suit the function and easy routing of connections.
Step 5: Connect components
Using lines to represent connections between components, follow standard conventions for connection styles. For instance, dotted lines should be for signals, while solid lines should be for power connections.
Step 6: Designators and labels
Each component should have a designator, and then you can add labels to the schematic for identification. It will then become easier to refer to specific parts while building the PCB and discussing the schematics.
Step 7: Check errors
Errors may occur during this process. Hence, reviewing the schematic is vital to ensure proper corrections. Omissions and mistakes can affect the appropriate functioning of the circuit.
Common PCB schematic software
Several software packages exist for the creation of a PCB schematic. The following are the most widely used PCB layout software:
- PADS (Power PCB and layout system) – supports simulation, 3D visualization, multiple design languages, and collaboration tools.
- OrCAD – supports multiple design languages, collaboration tools, simulation, 3D visualization, and collaboration tools.
- KiCAD – free and open-source tool supporting multiple design languages, collaboration tools, simulation, 3D visualization, and collaboration tools.
- EAGLE (Easily Accessible Graphical Layout Editor) – a user-friendly tool that offers multiple design languages, collaboration tools, simulation, 3D visualization, and collaboration tools.
- Altium Designer – a professional-grade tool that supports simulation, 3D visualization, multiple design languages, and collaboration tools.
Specific needs and preferences will dictate the choice of software to use. Try out different tools to settle on the one that suits you best.
PCB layout vs. schematic
The PCB layout is what creates the actual PCB. It helps to connect the components. A schematic is just a diagram that represents electronic components and circuits. It follows a logical way to show the components and how they connect.
The primary role of a PCB schematic is to comprehend the device’s functioning and assist in troubleshooting.
Both the layout and schematics, nonetheless, matter in developing and designing circuits/devices. While the schematic designs and plans, the layout implements the design. Both, ultimately, determine how the electronic device works.
A PCB schematic is a technical drawing showing the layout of the printed circuit board. It also displays the electrical connections flowing through the board. The entire design process depends on the correct schematics.
- Integrated circuit (IC)
- Transistor
- Diode
- Inductor
- Capacitor
- Resistor
- PADS (Power PCB and layout system)
- OrCAD
- KiCAD
- EAGLE (Easily Accessible Graphical Layout Editor)
- Altium Designer
Conclusion
An exemplary PCB schematic is imperative when designing and developing PCBs. The layout is equally just as important in the creation of functional PCBs. At IBE, we have been in PCBs and PCB assembly business for years and have the right experience to partner with you. Talk to us today about your PCB or PCBA needs so that we can help you reach milestones and develop quality constantly.
