TDK Introduces Power Inductors for Automotive LED HeadlightsSeptember 04, 2019 by Gary Elinoff
The SPM-VT series meets the high thermal and current demands of the automotive LED headlight environment.
The SPM-VT series is the latest edition to TDK’s lineup of metal-core, wire-wound power inductors. To meet the tough conditions prevailing in harsh automotive environments, these metal-core power conductors have a wide operating temperature range from -55 °C up to +155 °C.
Members of TDK’s SPM-VT series. Image from TDK
The units offer low DC resistance along with very small size when compared to ferrite wound type inductors. This is made possible due to the DC superimposition characteristics of metallic magnetic materials.
These inductors boast superior DC superposition characteristics in a compact size. TDK claims that the members of the SPM-VT series feature a rated current that is approximately two to three times higher than that of comparable high-temperature products.
Characteristics of LED Headlights
Modern adaptive LED headlights respond to changing conditions. These include low and high beams, daytime running lights and curve lighting. As such, they generally employ only one control circuit to drive all LED headlight functions.
Because of their low power consumption and multifunctional adaptability, LED headlights are now rapidly replacing conventional halogen and HID headlights. The DC-DC power converters needed by these multifunctional devices all require power inductors.
These initial members of the SPM-VT series of metal composite, wire-wound power inductors include:
The specifications of the individual series members are illustrated below:
*Isat: Based on the inductance change rate (30% lower than the initial figures)
** Itemp: Based on a temperature increase of 40 K
In addition, the datasheet for the SPM7054VT-470M-D reveals that it is currently available in four subtypes:
These will vary in terms of inductance and other characteristics, but they are the same size as described in the chart
- All members of the SPM-VT series are are compliant with AEC-Q200
- These units are vibration resistant to 30 G, an important factor in the tough automotive environment
For the Future
Whether all-electric, hybrid, or gas-powered, the electrification of the world’s fleet of passenger vehicles proceeds apace. As the functionality of LED headlights increases, they will inevitably replace their incandescent forebearers. Certainly, the number and types of power inductors needed will continue to grow.
To meet that demand, TDK will continue to expand its lineup of SPM power inductors. In the offing are more miniaturized inductors with planned dimensions of 7.0 x 6.5 x 4.5 mm and 5.3 x 5.1 x 3.0 mm.
Around the Industry
Due to the wide applicability of miniature inductors in the automotive industry, there are many participants. Here is one representative competitor.
Kemet’s METCOM Inductors SMD metal composite power inductors are AEC-Q200 qualified. Inductances range from 0.10µH to 47.00µH, and DC resistance values are as low as 1.5mΩ. The units can support currents up to 35.4 amps, and footprints are as small as 5.3mm x 5.00mm with heights as low as 2.0mm.