150ºC compatible chip ferrite beads suppress power line noise

Murata's BLM31KN_BH series of chip ferrite beads are aimed at the automotive market for use as noise suppression components in power line circuits installed in engine bays and LED headlights that require guaranteed performance at high temperatures up to 150ºC.

The number of motor control circuits (with brushes) or inverter circuits (brushless) has increased with the motorisation of powertrains, requiring noise suppression components that are capable of dealing with large currents. Furthermore, in order to reduce vehicle weight, the ECUs for engine systems and safety systems tend to be located in engine bays that reach high temperatures, and hence require noise suppression components capable of working in, and sustaining those high temperatures.

BLM31KN_BH series comes in a 3.2x1.6mm package that supports the large currents suitable for power lines (120 ohm / 4A at 125ºC) thanks to specially designed internal and external electrodes for use at temperatures up to 150ºC. The BLM31KN_BH series conforms to the all-important automotive test standard AEC-Q200, and is available within the range of -55 to 150ºC with derating. The beads’ impedance up to 1000 ohm is effective for noise suppression at 100MHz.