Murata has introduced the BLM18KN_EH series of chip ferrite beads for noise suppression in power lines at temperatures up to 175°C. Target automotive applications include engine and transmission electronic control units (ECUs) and turbo motor controllers. The components also meet AEC-Q200 qualification requirements.
The new line is available in a 0603 size with dimensions of 1.6 mm × 0.8 mm. The devices have low direct current resistance (Rdc) making them compatible with large currents and low power consumption. The solution also delivers a wide operating temperature range and a rated current from 740 mA to 4,000 mA (−55°C to +125°C), 490 mA to 2,600 mA (+150°C), and 10 mA (+175°C). The typical impedance at 100 MHz ranges from 26 Ω to 1000 Ω.
By selecting a ferrite material that does not lose its magnetic properties at high temperatures, combined with an electrode to suppress temperature-related deterioration, the BLM18KN_EH series conforms to the AEC-Q200 standard for use up to 175°C. This greatly improves design freedom allowing for the reduction of electromagnetic interference in high-temperature areas that were once not possible. An additional benefit of the new solution is its low DC resistance, which reduces heat generated and increases efficiency.