Advanced inductors from Taiyo Yuden

The MCOIL SMT inductors from Taiyo Yuden were big favorites of our Product of the Year committee. It isn't often that we see a significant breakthrough in an inductor, and the MAMK2520 and MDMK2020 MCOIL power inductors are significant. They are smaller and thinner than any other available. The 2.5 x 2.0-mm MAMK2520 and 2-mm-square MDMK2020 use a new type of metallic core and can handle higher current levels than other power inductors of their size.

The 2.2-μH MAMK2520T2R2M has a saturation current of 2,000 mA minimum and 2,300 mA typical — two times higher saturation current than similar parts in this 25 x 20-mm size. And, the devises are only 1.2 mm thick.

We asked the folks from Taiyo Yuden about the origin of their great design.

The Taiyo Yuden MCOIL design team

MCOIL was inspired by the development of new metallic magnetic materials that have the advantages of metal-composite materials, but with greatly improved dc bias characteristics. This was done by the R&D and product design teams, who were researching fundamental materials. Unlike many companies, Taiyo Yuden develops its core materials in house.

The popular metal composite power inductors have metallic magnetic particles mixed in their organic binders to isolate the particles themselves, to prevent the particles from going oxidized, and to secure the strength of inductors. MCOIL material offers the same level of insulation and oxidation prevention as the metal composite without the organic binders, thanks to oxidation layers which are formed on the surfaces of metallic magnetic particles. Besides, the thinness of oxidation layers, they yield high magnetic permeability, compared to metal composite types.

Approximately 30 people participated in the project at Taiyo Yuden's Nakanojo plant. Since this was the first use of the new metallic magnetic materials, the design went through many tests before being successfully launched.