BLM18BD421SH1D

Chip Ferrite Bead Overview

The BLM18BD421SH1D is a single-line ferrite chip bead from the Murata EMIFIL BLM18_H series, designed for surface-mount assembly in the 0603 (1608 metric) package. It provides an impedance of 420 Ohms with a 25% tolerance at a test frequency of 100 MHz. The component supports a maximum DC current of 250 mA and features a maximum DC resistance of 550 mOhms. It operates within a temperature range of -55°C to +125°C and holds AEC-Q200 qualification.

Chip Ferrite Bead Feature Summary

• Provides high-impedance noise suppression for signal lines in compact surface-mount designs
• Engineered for automotive reliability through AEC-Q200 qualification standards
• Optimized for low power loss applications via minimal DC resistance characteristics

Chip Ferrite Bead Applications

• Automotive electronic circuit noise filtering
• High-frequency signal line protection
• Compact consumer electronics EMI suppression

Chip Ferrite Bead Procurement Notes

Verify the specific suffix against official documentation to confirm exact electrical tolerances and packaging configurations. Ensure the selected variant matches the required impedance and current ratings for the target application. Cross-reference the manufacturer's part number guide to distinguish between similar series members that may share base identifiers but differ in performance specifications or physical dimensions.

Chip Ferrite Bead Selection Notes

Select this component when space constraints require a 0603 footprint while maintaining significant noise attenuation capabilities. The 250 mA current rating suits low-power signal paths rather than high-current power distribution lines. Consider the 420 Ohm impedance profile relative to the target noise frequency spectrum to ensure effective filtering without excessive signal degradation in the operational bandwidth.

Chip Ferrite Bead Part Context

This component belongs to the BLM18 series, which utilizes Murata's proprietary monolithic ferrite technology. The series is characterized by its ability to suppress electromagnetic interference in small form factors suitable for dense PCB layouts. The BLM18_H sub-series specifically targets applications requiring robust performance across wide temperature ranges and stringent automotive quality standards.

Chip Ferrite Bead Replacement Considerations

Official substitutes include BLM18BD421SN1D, which shares identical electrical parameters but differs in packaging format.