Top 10 PCB Design Mistakes and How to Avoid Them: A Beginner's Guide

Have you wondered how smartphones and smartwatches fit so much great stuff into such a little space? All thanks to PCB design! Look behind the curtain.

Consider PCB設計 as the blueprint for electronics. All the electronic parts operate together there. Imagine solving a puzzle where every piece must fit perfectly to work properly.

The catch: PCB design isn’t merely connecting the dots. It’s about first-time success. Mistakes cost time, money, and headaches to repair.

That’s why this post covers the top 10 PCB design mistakes beginners make. Not to worry! Not to scare you away from PCB design. Instead, we’ll provide you with the details and methods to overcome these issues. So, let’s get started. 

Top 10 PCB Design Mistakes and the Strategies to Avoid Them

Trace Width and Spacing

PCB Design Mistakes- Trace Width and Spacing

The trace width determines how much current it can carry without overheating. A narrow trace might cause signal degradation. The common mistake that designers can make is making thin traces for current, leading to performance issues. 

Besides, trace spacing is also an important factor that prevents electrical interfaces at higher frequencies. There is a chance of crosstalk in the traces close to each other. Excessive spacing can also make the PCB quality worse.

Strategies for Trace Width and Spacing

  • Check out the design guidelines for minimal trace width and spacing based on your manufacturing process and applications. 
  • Try to determine the maximum current each trace carries and thus size them accordingly. For example, traces that carry a larger current should be wider, while the サーキットボード for sensitive and high-impedance applications should be thinner. 
  • Maintain the proper spacing between the signal traces to minimize interface and crosstalk. For example, high-speed signals, analogue circuits, and differential pairs require some specific spacing.

コンポーネントの配置

Component placement can break functionality and device efficiency. Just think of it as placing furniture in a room where placement matters for functionality and flow.

In PCB, one common mistake that beginners make is placing the components too close to each other. This results in signal interface and overheating issues. 

The next mistake in PCB is overlooking the relationship between components, which can create a mess with performance. 

Strategies for Component Placement

Try to start by grouping the related components. For example, place the power-related components near each other. Try to have enough space between the components so that there is enough airflow.

Also, consider the orientation of components for optimal signal flow. And finally, don’t forget to double-check the component placement, which can save you tonnes of headaches later.

Vias and Holes

PCB Design-PCB hole and vias

Like the trace width, PCBビア require proper sizing. Sometimes designers neglect the importance of power via size. It results in various issues like manufacturability, thermal issues, and signal degradation. 

Using small-size vias can result in signal attenuation and high resistance. Besides, it can create electrical and mechanical conflicts too.

Strategies for Vias and Holes

  • Ensure the proper via size for current-carrying capacity and signal requirements.  For this consider factors like 銅厚 and plating requirements. 
  • Strategically place vias to minimize signal distortion and mechanical conflicts. 
  • Use thermal vias or pads to improve heat dissipation and prevent thermal difficulties, especially for high-power components or tightly packed designs.

The recommended via size for signal and power vias is:
0.3 mm to 0.5mm. 

For thermal vias:

0.6mm to 1.0mm can be used.

Decoupling

Decoupling Capacitor

For beginners, they often overlook the decoupling in PCB. 

Decoupling plays a great role in stabilizing power and ensuring signal integrity. They store energy sources for 集積回路 (ICs), which can reduce the voltage fluctuation and noise in the power supply lines. 

Designers place the decoupling capacitors far from ICs. The other mistake that designers make is selecting decoupling capacitors with insufficient voltage ratings or capacitance. It leads to insufficient noise suppression.

Strategies for Effective Decoupling

  • Place the decoupling capacitors close to the power point of the ICs. 
  • Try to use ceramic and electrolytic capacitors for wide frequency coverage. For example, for low-frequency transients, use electrolytes, and for 高周波 decoupling, use ceramic capacitors.
  • Select decoupling capacitors based on the IC and noise frequency needed.

 

Grounding and Power Planes

PCB power planes and grounds

Ground and power planes are the next important things to consider for the reliability and functionality of electronic circuits.

Beginners commonly make mistakes like inadequate grounding connections, neglecting proper grounding, and creating ground loops for high-frequency components. 

Other common errors include improper via placement, insufficient copper thickness, and overlooking the importance of decoupling capacitors. 

Strategies for Effective Grounding and Power Plane

  • Make sure to use dedicated ground planes. For example, keep the ground impedance low, and separate analog and digital ground areas.
  • For varying voltage levels, try to consider the multiple power planes. Optimize the copper thickness for handling the current. Then strategically place the decoupling capacitors to reduce the power fluctuations. 

 

Signal Routing

Beginners often ignore signal routing on the circuit board. It results in signal deterioration and interference from inappropriate trace length, impedance matching, or crosstalk.

Strategies for Proper Signal Routing

  • Follow signal routing guidelines for trace length, impedance matching, and sensitive signal separation. 
  • Try to avoid straight angles in traces, and to reduce signal distortion, try to use differential pairs for high-speed signals. 

 

Design Rule Check and Electrical Rule Check

A PCB design must undergo a Design Rule Check (DRC) and Electrical Rule Check (ERC) before finalization to guarantee it fulfills the requirements. These tests detect layout and electrical connection faults, saving costly production and operating errors. DRC and ERC ensure PCB stability and performance by exhaustively evaluating trace spacing, clearance, and electrical connectivity.

Strategies for DRC and ERC

Complete DRC and ERC checks with PCB CAD design software to find and fix layout and electrical issues. For this, you need to run the DRC in your PCB CAD software

 Regularly change デザインルール parameters to match manufacturing and design requirements.

Improper Thermal Management

Lack of thermal management in PCB design can cause component overheating, poor performance, and device failure. Effective thermal management is necessary to dissipate heat and ensure 電子部品 dependability.

Some of the thermal management solutions include; thermal vias, heat sinks, and relief pads. Designers can manage heat dissipation, minimize thermal hotspots, and assure PCB reliability and operation by using these methods.

Strategies for Proper Thermal Management

  • You can design the PCB layout to promote natural airflow. 
  • Also, conduct the thermal analysis during the design phase using PCB CAD simulation software to identify the thermal stress. 

You can check out the below tutorial for thermal PCB design tips:

結論

PCB design is complicated but profitable, but it demands careful attention to avoid mistakes. Beginners can improve design reliability and functionality by addressing trace width and spacing, component placement, vias and holes, decoupling, grounding and power planes, signal routing, DRC and ERC, and thermal management.

You need to follow the design guidelines and also check for some common errors that people repeat in PCB design. 

If you are a beginner, then you can overcome the obstacles by learning and updating the best practices. Feel free to check out FS PCBA for any PCB related services, or PCB design issue. 

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