Designing equipment to avoid interference and tolerate it.
EMC ensures equipment neither emits excess interference nor fails from external fields. Techniques: shielding, filtering, grounding, cable routing, ferrites, PCB layout. Standards (CISPR, FCC, IEC 61000) define limits and immunity tests.
Switch-mode supplies need EMI filters.
Electromagnetic compatibility keeps devices from interfering with each other and passes regulatory tests, which is essential before selling electronic products.
Designing equipment to avoid interference and tolerate it.
Electromagnetic compatibility keeps devices from interfering with each other and passes regulatory tests, which is essential before selling electronic products.
Emission is the interference a device creates, and immunity is its ability to tolerate interference from others. Both are tested.
Noise coupling depends on layout, cables and enclosure, so problems often show only when the complete product is built and tested.
Typical applications include adding filters and shielding to a motor drive to pass emission tests, designing a PCB layout that avoids crosstalk between a radio and a sensor and choosing a shielded cable for a sensitive instrument near a high-power inverter.
Study "Waveguides and antennas" first (topic 97 of 106 in Electrical Engineering). It covers the groundwork this topic builds on.
Conducted vs radiated emissions. ESD and surge immunity. Common-mode chokes.
Switch-mode supplies need EMI filters.
The next topic is "Insulation and dielectric breakdown", which builds directly on this one.
It is classed as Advanced in Electrical Engineering (topic 98 of 106). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Electrical Engineering.
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