TDK Unveils Small Automotive Power Inductors

TDK has expanded the BCL3520FT series of small power inductors for automotive power circuits.

Mass production began in December 2025. Designed for efficient ECU power supplies in ADAS and other automotive applications, the power inductor series leverages proprietary metallic magnetic materials and structural design to deliver low loss, high functionality, and compactness for harsh, high‑temperature environments.

Key highlights

• Industry-leading DC resistance: 5 mΩ (typ.) at 0.47 µH, ~15% lower than equivalent market products.
• High current capability: Rated current (Isat) of 10 A, ~28% higher than comparable products.
• High-temperature reliability: Operable up to +155 °C (upper guaranteed temperature limit).
• Automotive qualification: Compliant with AEC‑Q200.
• Compact footprint: 3.3 × 3.5 × 2.0 mm (L × W × T) for space‑constrained ECUs.

The series achieves industry‑leading electrical properties at 0.47 µH within a 3.3 × 3.5 × 2.0 mm package, featuring a typical DC resistance of 5 mΩ and Isat of 10 A. Flat wire windings reduce heat generation and power loss compared to round wire, contributing to higher current performance and reliability up to +155 °C.

Applications

• ADAS ECUs: Efficient power supply circuits in advanced driver‑assistance systems.
• xEV platforms: Electrified vehicle subsystems requiring compact, high‑reliability inductors.
• Automotive cameras: Space‑limited modules with stringent thermal requirements.

Features

• Low DC resistance: 5 mΩ (typ.) minimizes power loss.
• High current handling: 10 A Isat extends application range.
• Thermal robustness: Upper guaranteed temperature limit of +155 °C.
• Automotive compliance: AEC‑Q200 qualification.
• Compact form factor: 3.3 × 3.5 × 2.0 mm for dense assemblies.

Specifications

• Isat: Current based on inductance variation (30% lower than initial L).
• Itemp: Current based on temperature rise (ΔT = 40 K by self‑heating).