TDK Intros Common-Mode Choke Series Rated up to 1250 VDC

TDK has released the B82722V6*B040 series of high-voltage common-mode chokes designed to address EMI suppression in power electronics that operate at DC link voltages of up to 1250 V. As system voltages continue to increase in modern designs, managing conducted noise becomes more challenging, particularly in compact layouts where spacing and insulation requirements also have to be maintained.

The series is aimed at applications such as power converters, industrial motor drives, and switch-mode power supplies, especially those built around SiC and GaN power semiconductors. These devices operate at higher switching frequencies and voltages, which improves efficiency but also increases EMI. As a result, components like common-mode chokes will end up playing a more critical role in maintaining signal integrity and meeting compliance requirements without expanding PCB footprint.

TDK B82722V6*B040 high-voltage common-mode choke with ring-core winding structure for EMI suppression. Image used courtesy of TDK

High-Voltage Capability and Electrical Performance

The B82722V6*B040 choke series is rated for up to 1250 VDC (630 VAC), which makes it ideal for high-voltage DC link designs used in industrial drives and power conversion systems where efficiency and power density are increasing.

To support these conditions, the chokes use a current-compensated ring core design with multilayer solid insulation. They are tested to 3750 V DC line-to-line, providing the level of isolation needed to maintain safety and reliability in high-voltage environments, where insulation coordination is a key design consideration.

EMI Suppression and Magnetic Characteristics

The B82722V6*B040 series chokes are built to address both common-mode and symmetrical interference. The chokes offer inductance values ranging from 3.3 mH to 22 mH, and have rated currents from 0.85 A to 3.0 A at 70°C.

The B82722V^*B040 series also has a low stray inductance, typically around 0.6%, which helps reduce coupling effects that can contribute to unwanted noise. Combined with a high resonance frequency enabled by the winding technique, this allows the choke to remain effective across a wider frequency range, especially relevant in fast-switching SiC and GaN-based systems.

Impedance vs. frequency characteristics of the B82722V6*B040 series. Image used courtesy of TDK

Mechanical Design and Integration

The choke components measure about 23 × 15.5 × 24 mm, helping reduce PCB area while still maintaining the spacing and clearance required for higher-voltage designs. This is useful in power electronics for managing higher DC bus voltages and limited board space simultaneously, especially in more compact converter layouts.

Mechanical dimensions and pin configuration of the B82722V6*B040 high-voltage common-mode choke. Image used courtesy of TDK

The ferrite core is epoxy-coated and paired with a UL 94 V-0-rated plastic base, providing mechanical protection and meeting the expected flammability requirements in industrial applications. The parts are also suitable for wave soldering, so they can be integrated into standard through-hole manufacturing processes without requiring changes to assembly methods.

Application Fit and Standards Compliance

The series is designed for use in compact switch-mode power supplies, frequency converters, and general EMI filtering applications.

The B82722V6*B040 high-voltage common-mode choke is compliant with IEC 60938-2 and IEC/UL 60939-3, meeting the current safety and performance standards for EMI chokes. These types of chokes are typically used in input or DC link filtering stages, where controlling conducted emissions is necessary to meet regulatory requirements and maintain stable system operation.

TDK’s B82722V6*B040 series provides a high-voltage common-mode choke option that combines compact size, low stray inductance, and high resonance performance, and will also support up to 1250 V DC and compliance with relevant EMI standards. The B82722V6*B040 series is suited for power electronics designs where switching speeds, voltage levels, and space constraints must be managed together.