TDK enables compact 1250 V DC converter designs with a new high-voltage common-mode choke

TDK Corporation (TSE: 6762) presents the B82722V6*B040 series of new compact high-voltage, current-compensated ring-core double chokes. Designed primarily for rated DC voltages of up to 1250 V (630 V AC), these compact common-mode chokes (23 x 15.5 x 24 mm) effectively suppress EMI in next-generation applications. These include power converters, industrial motor drives, and switch-mode power supplies that often deploy SiC and GaN power semiconductors and feature elevated DC bus voltages, where insulation coordination and PCB space are critical.

The series covers nominal inductance values ranging from 3.3 mH to 22 mH, with rated currents between 0.85 A and 3.0 A at a rated ambient temperature of +70 °C. Multilayer solid insulation construction and testing with voltages of 3,750 V (line-to-line) ensure robust electrical isolation. Thanks to the special automated winding technique, these chokes feature high resonance frequency characteristics and a typical stray inductance of around 0.6%, helping to suppress symmetrical interference.

The epoxy coating of the ferrite core and the plastic header comply with UL 94 V-0. The design fulfills the latest IEC 60938-2 and IEC/UL 60939-3 safety requirements for EMI chokes and filters. Suitable for wave soldering and offered in a compact vertical design, the B82722V6*B040 series enables engineers to realize 1250 V DC high-voltage architectures without increasing the PCB footprint.

Main applications 

• Suppression of common-mode interference

• Compact switch-mode applications

• Frequency converters

Main features and benefits 

• Very high voltage rating

• High resonance frequency due to special winding technique

• Approx. 0.6% stray inductance for symmetrical interference suppression

• Space-saving design

• Suitable for wave soldering

• Design complies with IEC 60938-2 (630 V AC, 50/60 Hz, PIII; 1250 V DC-link, PII)

• RoHS-compatible