Best Practice for Advanced PCB Design
The idea of designing a simple LED is very different from a full-featured embedded controller with high-speed connectivity such as USB or Ethernet. Incorporating wireless functionality only complicates the PCB layout. Designing advanced printed circuit boards can be very challenging and there is a risk of error that leads to multiple revisions when you are not aware of best practices.
1.High Speed Signal
When you design with high-speed signals like USB or Ethernet, there is a risk of onboard electrical interference if the PCB layout is incorrect. For high-speed design, component placement is very important. High-speed components in advanced circuit design should be placed as close as possible to the boards center to avoid EMI radiation. High-speed connections should also be kept to a minimum length to prevent interference.
A single ground plane can work perfectly for a simple LED. However, try that on an industrial design involving analog and digital signals can result in unstable readings of analog sensor values. It is a common knowledge that ground isolation must be provided between noisy components and sensitive analog parts. Different ground planes should only be connected at a single point.
In an advanced circuit design, you may be dealing with dozens of internal and external critical communication signals. If the route is incorrect, these signals may be coupled to each other. The differential signals should always be routed parallel to each other and matched in length. Communication signals should always be routed at a vertical angle between layers to provide crosstalk.
Careful handling of advanced PCB designs is important because errors can easily slip past PCB software checks, resulting in wasted time and design revisions.