Electromagnetic shielding of portable power supply

How do you shield a power supply?

Shielding the source using thin conductive layers is most effective. Inductive coupling: This transmission path is quite common in switched-mode power supplies since high-frequency currents in the inductors can cause strong magnetic fields at higher frequencies, where the coupling factors can be higher.

What is EMI shielding?

Electromagnetic interference (EMI) shielding is critical in electronic applications. However, the currently available EMI shielding materials are restricted in customizability and application flexibility. Recent advances in manufacturing technologies have provided a unique path to achieve the custom creation of EMI shielding solutions.

What is low frequency magnetic field shielding?

Low frequency magnetic field shielding requires a material with a thin skin depth. Increasing shield thickness improves shielding until the material becomes thick enough. “Unobtainium” – has the same skin depth as iron except the relative permeability of the material is 1. but the relative conductivity is 688.

What materials are used for EMI shielding?

Raw materials for EMI shielding. EMI shielding solutions traditionally rely on metals (e.g., copper, aluminum, iron, nickel) because they have ultrahigh electrical conductivity and can effectively reflect and attenuate electromagnetic waves (Fig. 4a, b) .

Do high-performance EMI shielding materials cause secondary electromagnetic pollution?

Previous efforts to design high-performance EMI shielding materials were mainly focused on increasing their electrical conductivity, which can significantly enlarge the impedance mismatching and enhance the reflection to enable high EMI SE. However, the reflected radiation may cause secondary electromagnetic pollution.

What is the difference between magnetic shielding and electric shielding?

Magnetic shielding is less effective than electric shielding since the absorption depth is smaller, requiring thicker materials. Inductive coupling is best addressed at the source. Wave coupling: Here, the noise typically has a high frequency, and is transmitted via an electromagnetic wave.