Why do we need EMC?

Electromagnetic compatibility (EMC) has become a major challenge for equipment and switching power supply designers. As more and more countries apply EMC regulations on products entering their respective markets, EMC compliance of a product has become a major factor defining its acceptance.

The EMC challenge has two parts:

1. Suppression of interference at the source.
2. Making devices or systems immune to EMI.

There are three general approaches to suppressing of EMI:

1. Good screening for radiated EMI.
2. Proper earthing.
3. Filtering of power and signal lines to reduce conducted EMI.