3.3 µH, 5.4 A — the DC bias and saturation ceiling
The DFEH7030D-3R3M=P3 is a shielded surface-mount power inductor from Murata's DFEH7030D series, rated for 3.3 µH at 100 kHz with a ±20% tolerance. Its 5.4 A continuous current rating defines the DC load the inductor can carry before the copper losses push the temperature rise past the design margin — the 29 mOhm max DCR is the number to plug into your I²R thermal budget. The saturation current is 7.1 A, the hard ceiling where the iron powder core saturates and inductance drops sharply. For a buck converter switching at 200 kHz–2 MHz, the peak inductor current under transient load must stay below this value to maintain output regulation.
AEC-Q200 and the 155°C ceiling — where it fits
The -40°C to +155°C operating range covers under-hood and engine-bay environments where ambient temperatures can hit 125°C with self-heating margin. The shielded construction contains the magnetic flux, reducing radiated EMI that could couple into nearby signal traces or fail CISPR 25 radiated emissions in an automotive ECU. The iron powder core offers higher saturation flux density than ferrite, but core loss rises faster with frequency — keep the switching frequency under 2 MHz for acceptable efficiency.
Footprint and board integration
The 'Nonstandard' package designation means the pad layout is specific to this series; use the recommended land pattern from the DFEH7030D datasheet, not a generic 7030 footprint. Available in Tape & Reel and Cut Tape packaging for both prototyping and production reels.