TDK Corp. has developed four new series of miniature, low-profile thin-film metal power inductors featuring up to twice the rated current and half the DC resistance of comparable ferrite inductors. The new TDK TFM family is available in four form factors, including IEC 1608, which at 1.6 by 0.8 by 1.0 mm³ is the world’s smallest metal power inductor. The other case sizes in the lineup are 2520, 2016 and 2012. The new TFM thin-film metal power inductors feature inductances ranging from 0.47 µH to 2.2 µH and rated currents from 0.8 A to 4.0 A, providing customers with a wide selection for various needs. Mass production began in September 2012.
While the core material of inductors is predominantly ferrite, TDK has harnessed its proprietary materials technology to create a magnetic metal with high saturation flux density, enabling improved electrical properties in a very compact component. Compared to the previous ferrite type (TFC252010/2.2µH), for example, the rated current has been doubled without sacrificing extremely stable DC superposition characteristics. TDK’s thin-film technology enables the creation of a high-precision coil pattern in the wafer process. Combined with advanced plating technology, this results in reduced DC resistance, thus cutting losses. In smartphones, for example, with their multiple power supply inductors, the use of the new TDK TFM thin-film metal power inductors will thus contribute toward improved power supply efficiency and longer battery life.
Because of their high rated current, small footprint and low profile, the TFM thin-film metal power inductors are well suited for use in the DC-DC converters that serve as power supplies in smartphones, tablet PCs and mobile devices.