When it comes to creating electronic devices designing printed circuit boards plays a crucial role that cannot be understated. Every stage in the PCB design process significantly influences the following manufacturing and assembly steps, determines the reliability of the end product. In this article, we will show you the main steps in designing a PCB, the key point of different types of PCB design, and how we can help you with your PCB design.
How to Approach PCB Design?
QFPCB as a PCB specialist with 16 years of experience, can provide one-stop service for PCB design, manufacturing, assembly, and component selection. We has outlined 7 steps, for circuit board design to facilitate a progression of your project from desgin to manufacturing.
First Step: Defining Key Electrical Parameters for PCB Design
Early in the design process, we need to determine the maximum expected current of the PCB and the operating voltage of the system to ensure that the rated current capability of the alignment and component is sufficient to prevent overheating or damage. Next, it is important to identify whether the signal type is digital, analog, or mixed, and to control the impedance of the alignment according to the need for high speed or high frequency signal, thus improving signal integrity and reducing reflection and noise. In addition, shielding strategy are developed based on EMC.
These are just some of the key point in design, but of course there are many other factors to consider. If you need more indepth professional advice, you can always contact QFPCB’s professional engineer for a consultation.
Second Step: Designing the Schematic
Whether you’re using a template or starting from scratch, the first step in creating a printed circuit board (PCB) is designing the schematic, it serves as the foundation for the entire design. It essentially representing the electrical design for the PCB’s purpose and functionality. The schematic details which components are used—such as resistors, capacitors, inductors, connectors, and integrated circuits (ICs)—and how they are interconnected.
For PCBs with more complex designs, hierarchical schematics can map out how components relate across multiple levels of design. In short, the schematic provides a clear and organized way to define and modify circuit connections, making it easier to manage the design structure. Moreover, as circuit network become more intricate, adding annotations to the schematic is crucial. Clear and descriptive net names help you track component connection, making placement and routing more efficient.
Third Step: Capturing the Schematic
If the schematic serves as the project’s blueprint, then schematic capture is the process of turning that blueprint into a detailed construction plan. This step is not only does it ensure accurate and functional electrical connections, but it also makes the design easy for team members to understand while offering clear guidance for manufacturers. QFPCB advise considering the following key points during schematic capture:
1. Ensure Consistent Logical Flow
When organizing component symbol and connecting network in the schematic, it’s vital to maintain consistent logical flow and connectivity. This is particularly vital for high-speed circuits, as the PCB layout later relies heavily on how signal paths are arranged in the schematic.
2. Strategic Symbol Placement
When placing symbol, make sure there’s enough space to keep network connections clear and readable. This prevent confusion over pin numbers and network names, setting the stage for a smooth design process.
3. Flexible Adjustments
Don’t stick rigidly to the initial placement of symbols and networks—adjust them as needed for better organization. With robust schematic capture tools (like Mentor PADS®, Allegro,Kicad or Altium), you can easily move symbols and tweak circuit regions without worrying about overlapping reference designators, part numbers, or text.
4. Define Rules and Constraints Early
While most design rules don’t kick in until the PCB layout phase, defining categories for networks and components during schematic capture helps the layout stage to refers specific constraints, ensuring the final design aligns with project requirements.
5. Include Essential Information
Beyond circuit connection, your schematic should include key project details like product numbers, revision levels, contact info, and copyright data. This information is important for later stage like manufacturing and maintenance. At QFPCB, we will ensure this information is accurate.
6. Conduct Design Rule Checks (DRC)
Running a DRC during schematic design is vital for catching issues like missing pin connections. QFPCB rigorously enforces DRC protocols, ensuring the schematic is error-free before moving on to layout, ultimately delivering reliable designs to our clients.