During the design and manufacturing process of PCB Circuit Board, high-frequency interference is a common problem that needs to be taken seriously. In order to effectively avoid high-frequency interference, the following are some specific strategies and measures:
1. Layout and wiring strategy
Separate analog circuits from digital circuits: Separate the ground and power supply lines of analog circuits and digital circuits to reduce mutual interference. This layout method helps to reduce the impact of high-frequency signals on analog circuits.
Optimize high-frequency circuit wiring: Minimize the length and amplitude of high-frequency circuit wiring to reduce signal loss and interference during transmission. High-speed signal lines should be avoided from being parallel to other signal lines to reduce electromagnetic coupling.
Differential transmission lines or shielded transmission lines: When designing high-speed transmission lines, differential transmission lines or shielded transmission lines can reduce the impact of crosstalk. The layout and routing of differential signal lines should be kept symmetrical, and the spacing between signal lines should be reduced to reduce electromagnetic coupling.
2. Grounding and filtering measures
Separate digital ground from analog ground: If there are both logic circuits and linear circuits on the circuit board, they should be separated as much as possible. The ground of low-frequency circuits should be connected to the ground at a single point in parallel as much as possible, and high-frequency circuits should be connected to the ground at multiple points in series. The ground wire should be short and thick.
Add power supply filters: Add appropriate RC or LC filters at the power input to reduce the impact of high-frequency noise on the circuit.
3. Shielding and isolation
Use shielding materials: When possible, use shielding materials such as shielded wires or metal boxes for high-speed signal lines or key components to reduce electromagnetic radiation and crosstalk.
Insert a ground wire or ground plane: Insert a ground wire or ground plane between two lines with severe crosstalk, which can play an isolation role and reduce crosstalk.
4. Other considerations
Choose suitable materials and components: Choose materials and components with low noise, high isolation and other characteristics to reduce the possibility of high-frequency interference.
Reasonably set the wiring layer: Set different wiring layers for signals of different rates, and reasonably set the plane layer to reduce mutual interference between signals.
In summary, avoiding high-frequency interference on PCB Circuit Board requires comprehensive consideration of layout, wiring, grounding, filtering, shielding and isolation, and taking appropriate strategies and measures to ensure the performance and stability of the circuit board.
