Three Main Causes of Electromagnetic Interference

Three Main Causes of Electromagnetic Interference

Electromagnetic interference, or EMI, disrupts devices’ sensitive internal mechanisms and prevents them from functioning properly. Electronics need complete shielding to protect them from EMI, but you may wonder where EMI comes from in the first place. Read our brief guide to the three main causes of electromagnetic interference for more clarity on the subject.

Natural EMI

Many people think of other devices as the principle sources of EMI, but natural phenomena around us can emit EMI in several ways. Precipitation such as a rainstorm or snowstorm carries electrical static. When vehicles and other electronics encounter this, they build up a charge and emit EMI.

Beyond our world, stars and other nearby celestial bodies also emit natural EMI. Significant levels of solar radiation strike occasionally, while larger planets such as Jupiter emit appreciable EMI when they approach Earth. Many modern devices maintain their functionality when natural EMI is high, but this does impair older devices somewhat. Overall, engineers don’t implement device shielding to mitigate natural EMI because it isn’t a significant threat.

Human-Made EMI

The second type of EMI is human-made in the sense that manufactured devices and large-scale electrical systems emit interference. This encompasses every electronic assembly, from power lines to handheld devices. Any time these electronic assembly signals meet each other at the same frequency, they disrupt each other, depending on their relative strength. This is the major form of electromagnetic interference that shielding techniques such as vacuum metalizing limit. Because human-made EMI poses such a threat, some militaries intentionally weaponize it to inhibit enemy electronics.

Inherent EMI

The last of the three main causes of electromagnetic interference is inherent EMI. Inherent EMI is more difficult to remedy because it originates from the device itself. Essentially, devices’ internal electrical systems interact with other internal features, even within a shield or conductive coating.

If you need help limiting the effects of either human-made EMI or inherent EMI, consider contacting us at Deep Coat to help protect your electronics. We offer exceptional EMI coating services on both electronic assembly housings and PCB shields, which are backed by our team’s years of specialized knowledge and flexibility.