Murata Korea Eases Developer Design Burden with EMI Suppression Components and Technical Support

As electronic devices become increasingly miniaturized and faster, electromagnetic interference (EMI) is emerging as a key challenge in product development. In particular, high-frequency noise is an unavoidable design variable in circuits based on high-speed switching semiconductors such as GaN (gallium nitride) and SiC (silicon carbide). Consequently, the importance of EMI countermeasure components for reliably passing EMC (electromagnetic compatibility) tests is growing.

Murata Electronics Korea announced that it is providing solutions to deal with wideband noise through a lineup of EMI suppression components such as ferrite beads, common mode chokes (CMCCs), and power inductors, and is increasing the design efficiency of developers through its self-developed simulation tools and EMC test support environment.

According to Murata, EMI is divided into conductive noise and radiated noise, and can cause interference with external devices or product malfunction through various paths such as switching power circuits, communication lines, and PCB paths. In particular, the high di/dt and dv/dt characteristics of GaN/SiC devices cause strong EMI in the mid- and high-frequency bands, which is difficult to control with a simple filter.

Noise filters can be designed in various shapes depending on the frequency to be blocked.
Understanding its characteristics is key to design.

Three representative products for EMI environmental control

Murata presents design measures centered on the following three products for EMI environment control.

Ferrite Bead: Absorbs and attenuates high-frequency noise in the DC-DC converter power line, and has a diverse lineup including the BLM-H/G series that can support up to the GHz band.

Measurement examples showing how radiation noise levels vary depending on the application of different filter configurations.
In particular, three-terminal capacitors are excellent at reducing high-frequency noise.

Common Mode Choke (CMCC): Cancels out the common mode current transmitted through the cable, thereby blocking EMI radiated to the outside.

Power inductors and RF inductorsDuct: It suppresses magnetic fields by minimizing current loops and blocks noise propagation within the circuit.

"Tackling EMI issues in specific frequency bands requires more than simply addressing a single component. Accurately identifying noise propagation paths and their causes throughout the entire system is paramount," emphasized Yoon Hyun-joong, a technical support team member at Murata Electronics Korea. He added, "Murata provides comprehensive solutions that encompass simulation, measurement, and data provision, helping developers minimize EMI risks from the design stage."

Murata offers a simulation tool called "Simsurfing" to help designers consider EMI from the early design stages. This tool can predict component performance based on a variety of data, including SPICE models, S-parameters, and impedance characteristics. Murata Electronics Korea also establishes its own EMC testing environment to support customers in verifying EMI performance in advance during the product development stage.

“As electronic devices become more complex and smaller, it becomes more difficult for designers to notice EMI issues,” said Yoon. “Murata offers a wide range of EMI components, providing customized solutions for a wide range of applications, from automotive electronics to communications infrastructure.”

Murata stated, “No matter how precise the circuit is, if the PCB layout or grounding design is inadequate, it can fail the EMI test,” and explained, “The most effective countermeasure is to adhere to basic design principles such as reducing loop inductance, optimizing stack-up, and securing a ground plane.”

Meanwhile, Murata is simultaneously enhancing the performance and miniaturization of EMI components to respond to various high-speed signal environments such as mobile devices, automotive electronics, industrial equipment, 5G infrastructure, and electric vehicles. Recently, it has also expanded its RF inductor lineup to suppress internal noise generated in high-frequency communication environments.

Noise does not originate from a single circuit, but is transmitted through various paths throughout the system.
Filter placement should be approached from a holistic structural perspective.

As electronic devices become more complex, EMI sources and propagation paths become more diverse. Regarding this, Murata emphasized that “finding and suppressing even unknown noise is a future task,” and announced plans to continue developing an integrated EMI response system that includes simulation, measurement, and guidelines in the future.