Electromagnetic Compatibility (EMC) Design for PCB Boards

Electromagnetic compatibility (EMC) design for PCB boards is crucial not only for ensuring a reliable working circuit but also for minimizing electromagnetic radiation and ensuring compliance with relevant standards.

Types of Radiation from PCB Boards:

• Differential-Mode Radiation: This occurs when operating current flows through the signal loop in a differential mode, leading to differential-mode radiation.
• Common-Mode Radiation: When the potential of a signal-transmitting conductor differs from that of an adjacent conductor, common-mode radiation is generated.

Radiation from PCB traces and “I/O” cables primarily contributes to electromagnetic radiation. Both common-mode and differential-mode currents play a role in generating radiation, resulting in differential-mode and common-mode radiation.

Correction Wire Calculation Models:

The ideal models for radiation estimation may lead to errors in the near field. Correction wire calculation models for both near-field and far-field regions help address these inaccuracies.

Meeting Electromagnetic Compatibility Standards:

Electromagnetic compatibility standards typically characterize radiation strength by electric field strength. By controlling parameters such as differential mode current, frequency, and loop area, designers can reduce both differential-mode and common-mode radiation to meet standards.

Common mode choke coils and cable length adjustments are practical solutions for reducing common mode radiation on PCB boards.