TDK introduces thin permalloy film for low-frequency noise shielding

TDK Corporation extended its Flexield family of permalloy thin film sheets with the new IPM01 series. This series features high permeability and high loss in a lightweight and 0.006 mm ultra-thin design. The new material effectively shields low-frequency band noise, an increasing issue in electric vehicles (EVs). Mass production began this month, May 2024.

Electronic subsystems for information, communications, and navigation have been added to gas-powered automobiles over the years. These subsystems generate high-frequency noise measured in megahertz (MHz). EVs integrate those electronic subsystems but replace internal combustion engines with electric motors and inverters that generate lower-frequency noise in the kilohertz (KHz) range. Conventional noise suppression in the kHz band requires thick, bulky, and heavy metal shielding materials, which conflict with EVs’ priorities of minimizing size and weight.

The new IPM01 series is made of a permalloy alloy with extremely high permeability formed into thin film sheets. This allows it to suppress low-frequency band noise more effectively than conventional shielding materials and metal shields while reducing weight in automobiles. Compared to conventional TDK products, the thickness is reduced by about 80%, the weight by 90%, and the shielding effect is improved by 65% at 1MHz.

This new permalloy will find applications beyond the automotive market. As electronic equipment becomes smaller, thinner, and more multifunctional, noise suppression is increasingly important for smartphones and other devices. Using TDK’s permalloy sheet, it is possible to suppress noise at one-fifth the thickness of conventional products.

The IPM01 series in the Flexield family is available as sheet material and custom shapes. TDK will continue contributing to market needs by providing roll products and expanding its high-temperature lineup.