PMH1812-121

Overview

The Bourns PMH1812-121 is a high-current surface-mount ferrite bead designed for electromagnetic interference suppression. It features an impedance of 120 Ohms at a test frequency of 100 MHz with a tolerance of 25%. The component supports a maximum DC current rating of 3 A and maintains a low maximum DC resistance of 30 mOhms. It operates within a temperature range of -55°C to +125°C and utilizes an 1812 package footprint.

Feature Summary

• High current handling capability suitable for power line filtering
• Low DC resistance minimizes voltage drop in series applications
• Wide operating temperature range ensures reliability in harsh environments

Applications

• Power supply output filtering
• DC-DC converter noise suppression
• High-speed digital signal line protection

Procurement Notes

Verify the specific datasheet version for the PMH1812-121, as some sources indicate it may be obsolete or have limited availability. Confirm RoHS compliance status directly with the manufacturer or authorized distributors, as conflicting information exists regarding its lead-free status. Ensure the supplier provides authentic components from Bourns Inc. to guarantee performance specifications are met.

Selection Notes

Select this component when a 120 Ohm impedance at 100 MHz is required for high-current applications up to 3 A. The 1812 package offers a balance between current capacity and board space. Compare against similar MH series parts if lower current ratings are acceptable, or consider alternative packages if higher current handling is needed.

Part Context

This part belongs to the Bourns PMH series of high-current ferrite beads. These components are engineered for effective EMI suppression in compact surface-mount designs. The series is commonly used in consumer electronics, industrial controls, and automotive systems where reliable noise filtering is critical for signal integrity.

Replacement Considerations

Check for direct substitutes within the Bourns MH series or other manufacturers' 1812 ferrite beads with matching 120 Ohm impedance and 3 A current ratings. Verify that any replacement meets the same thermal and electrical specifications.