TDK enables 1250 V DC designs with compact EMI chokes

Power electronics applications such as industrial motor drives, switch-mode power supplies, and high-voltage DC converters increasingly require compact, high-efficiency designs capable of handling elevated DC bus voltages. In this context, TDK Corporation has introduced a new series of high-voltage common-mode chokes designed to support 1250 V DC architectures while maintaining electromagnetic compatibility (EMC) and minimizing PCB footprint.

The B82722V6*B040 series consists of current-compensated ring-core double chokes optimized for EMI suppression in next-generation systems, particularly those using silicon carbide (SiC) and gallium nitride (GaN) power semiconductors.

High-voltage EMI suppression for compact converter designs
The new choke series is rated for DC voltages up to 1250 V (and 630 V AC), addressing the insulation and interference challenges associated with higher DC-link voltages in modern power conversion systems.

Despite these high voltage ratings, the components maintain compact dimensions of 23 × 15.5 × 24 mm, enabling integration into space-constrained designs without increasing PCB area. This is particularly relevant for applications where power density and miniaturization are critical design parameters.

Electrical performance and interference control
The series offers nominal inductance values ranging from 3.3 mH to 22 mH, with rated currents between 0.85 A and 3.0 A at +70 °C ambient temperature, allowing engineers to select appropriate configurations based on application requirements.

A key design feature is the use of an automated winding technique that enhances resonance frequency characteristics and reduces stray inductance to approximately 0.6%. This contributes to improved suppression of both common-mode and symmetrical interference, which is essential in high-frequency switching environments typical of SiC and GaN-based systems.

Insulation and safety compliance
To ensure reliable operation under high-voltage conditions, the chokes incorporate multilayer solid insulation and are tested with 3,750 V line-to-line, supporting robust electrical isolation.

The design complies with IEC 60938-2 and IEC/UL 60939-3 standards for EMI suppression components. In addition, the ferrite core is coated with epoxy and combined with a plastic header meeting UL 94 V-0 flammability requirements, ensuring suitability for safety-critical applications.

Integration in industrial power electronics
The vertical design and compatibility with wave soldering facilitate straightforward integration into standard manufacturing processes. These characteristics make the series suitable for:

By combining high voltage capability, compact form factor, and improved EMI suppression, the new choke series enables engineers to design high-voltage DC systems without increasing board space, supporting the ongoing trend toward higher power density in industrial and energy applications.

Edited by Natania Lyngdoh, Induportals Editor — Adapted by AI.

www.tdk-electronics.tdk.com