Magnetic inductor B82464D6

DCelectrically isolatingdirect current

Introduction
Dual coupled inductors are used in non-isolated DC/DC converter topologies, as storage chokes or as transformers in flyback converters, and as common-mode inductors in power lines. These series feature coupling factors up to 99% and functional isolation between windings up to 500 V.

Key features

• High rated currents up to 7.05 A
• Saturation current up to 16.1 A (series dependent)
• Very low RDC values down to 0.018 Ω
• Coupling factor up to 99%
• Functional isolation between windings up to 500 V
• Maximum operating temperature up to 150 °C

Construction

• Tight magnetic coupling of the two windings
• Laser-welded winding connections
• Design optimised for mechanical and thermal robustness

Flexible usage

• 1:1 transformer application
• Two single inductors configured in series or parallel
• Common-mode or differential applications in multiphase converters

Overview of available package sizes and electrical ranges
Package (mm)

• 12.5 x 12.5 x 10.5
• 12.5 x 12.5 x 8.5
• 10.4 x 10.4 x 6.3
• 7.3 x 7.3 x 4.8

Inductance (µH) ranges by size

• 3.9 – 47 µH
• 2.0 – 100 µH
• 2.2 – 47 µH
• 2.2 – 47 µH

Saturation current (A) ranges by size

• 4.7 – 16.1 A
• 2.2 – 15 A
• 1.71 – 6.17 A
• 1.1 – 5.6 A

Frequently Asked Questions (selection)
What is a coupled inductor?
A coupled inductor contains two windings on a common core so that L1 and L2 are magnetically linked; energy stored in the core can be shared between windings. The magnetic coupling efficiency is described by the coupling factor k.

How is the coupling coefficient defined?
The coupling coefficient k quantifies the efficiency of magnetic coupling between windings and is calculated from the inductances of individual and combined windings (refer to manufacturer technical notes for the exact formula).

What are the benefits of using a coupled inductor?
Close coupling splits ripple current between windings, allowing a lower required inductance per winding. Using a dual inductor instead of two separate inductors can reduce component count and save PCB space.

DC/DC converter topologies (examples of applications)
SEPIC
Suitable for battery-powered and automotive applications where output may be above or below input; coupled inductors reduce ripple current and core losses.

ZETA
ZETA converters offer continuous output current with low ripple; non-isolated and typically implemented with a single buck controller IC.

CuK
CuK topologies provide inverted or regulated outputs with continuous current and low ripple; not isolated from input.

Flyback
Used as storage choke or transformer in flyback converters; can provide functional isolation up to 500 V. Flyback designs require careful EMC filtering due to switching voltage peaks.

Multi-Output Buck
Coupled inductors enable auxiliary or secondary outputs from a single buck regulator, reducing board space and component count.

Technical specifications

• Coupling factor: up to 99%
• Functional isolation voltage between windings: up to 500 V
• Inductance ranges: 2.0 µH to 100 µH (series dependent)
• Saturation current (typical): up to 16.1 A (series dependent)
• Rated currents (typical): up to 7.05 A
• DC resistance (RDC): down to 0.018 Ω
• Maximum operating temperature: up to 150 °C
• Design options: magnetically shielded, shielded & coupled
• Mechanical features: laser-welded windings, mechanical and thermal robustness