TDK Corporation has launched the EPCOS SurfIND series, a new range of current-compensated ring-core double chokes for high currents and surface mounting (ordering code: B82725S2*A/B).
SurfIND offers an SMD solution for those who rely on reflow soldering (commonly used in industrial drives and emerging EV power systems), where high-current, common-mode chokes are typically large and heavy.
These components can filter common-mode noise for rated currents from 24 to 36 A at a temperature of +70° C. With additional cooling, even higher currents can be achieved, making them suitable for demanding applications — like EV onboard chargers and inverters. This is easy to implement as the top side can serve as a direct interface for a heat sink.
For applications with a voltage of up to 250 V (ac), the nominal inductance ranges from 120 µH to 820 µH across seven variants. With stray inductance of up to one percent of the nominal inductance, these chokes dampen differential-mode noise, an essential feature for maintaining reliable power electronics in EVs.
All components meet IEC/EN 60938-2 standards and share a compact footprint of 40 x 38 mm (L x W), with heights of 20.7 mm for A types and 22.3 mm for B types. Their typical resistance ranges from 0.78 to 2.21 mΩ. IThe rated inductance drops by less than 10% at rated current with DC magnetic bias at +20 °C.
SurfIND chokes are mounted on a plastic baseplate, with a ferrite core coated in epoxy to insulate it from the windings; both materials are UL 94 V-0 approved. The special design of the connection wiring eliminates the need for adhesives, while self-leading SMD leads ensure easy reflow soldering to PCBs.
Applications
- Suppression of common-mode interferences
- Switch mode power conversion applications
- Frequency-variable drives
- Onboard chargers and inverters for EVs
Features
- High rated currents at high temperatures
- Low profile with defined height dimensions
- Self-leaded SMD terminals suitable for reflow soldering
- Ferrite core with epoxy coating and plastic base plate (UL 94 V-0)
- Approx. 0.6 to 1% stray inductance for differential-mode noise suppression
Filed Under: Technology News