Murata Power Solutions 18684C Equivalent & Substitute Parts

Part Overview

The Murata Power Solutions 18684C is a 680 µH unshielded wirewound inductor rated for 530 mA with a maximum DC resistance of 630mOhm, designed for through-hole axial mounting. This component is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements. The 18684C operates across a temperature range of 0°C to 70°C and is RoHS compliant with unlimited moisture sensitivity rating.

Substiute Parts

18684C

Murata Power Solutions Inc.In Stock: 86118684C Datasheet

Current PartRFQ

5900-681-RC

Bourns Inc.In Stock: 15345900-681-RC Datasheet

MFR RecommendedRFQ

AIAP-02-681K

Abracon LLCIn Stock: 781AIAP-02-681K Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 18684C is determined by the following critical parameters:

• Inductance Value: Must be 680 µH with ±10% tolerance
• Mounting Type: Must be through-hole axial configuration
• Shielding: Must be unshielded
• Current Rating: Must meet or exceed 530 mA minimum requirement
• DC Resistance: Lower DCR values are acceptable; higher values require circuit validation
• RoHS Compliance: Must maintain RoHS compliance status

The substitute parts listed below satisfy these core electrical and mechanical requirements while offering improved performance characteristics or active product status.

Parameter Comparison

Engineering Selection Recommendations

Bourns 5900-681-RC: This substitute offers active product status with improved current handling capability (900 mA versus 530 mA) and lower DC resistance (515mOhm versus 630mOhm). The extended operating temperature range (-55°C to 105°C) provides greater thermal flexibility. ROHS3 compliance ensures regulatory alignment with current standards. The drum core ferrite construction delivers superior performance characteristics while maintaining the required 680 µH inductance and ±10% tolerance.

Abracon AIAP-02-681K: This substitute maintains active product status with ROHS3 compliance. The compact axial form factor (0.252" diameter) offers space-saving advantages in board layouts. However, the elevated DC resistance (1.61Ohm maximum) represents a significant increase from the original specification and requires circuit-level validation to ensure acceptable power dissipation and voltage drop characteristics. Current rating of 490 mA falls below the original 530 mA specification and may limit application scope.

Frequently Asked Questions (FAQ)

Q: Can the Bourns 5900-681-RC directly replace the Murata 18684C?

A: Yes. The 5900-681-RC meets all critical substitution parameters: identical 680 µH inductance with ±10% tolerance, unshielded axial through-hole configuration, and current rating exceeding the original 530 mA requirement. The lower DC resistance and extended temperature range represent performance improvements.

Q: Is the Abracon AIAP-02-681K suitable for all 18684C applications?

A: The AIAP-02-681K satisfies the core inductance and mounting requirements but presents two considerations: the 490 mA current rating is below the original 530 mA specification, and the 1.61Ohm DC resistance is significantly higher than the original 630mOhm specification. Application suitability depends on circuit current demands and acceptable power dissipation levels.

Q: What is the impact of DC resistance differences between substitutes?

A: DC resistance directly affects power dissipation and voltage drop across the inductor. The Bourns 5900-681-RC (515mOhm) provides lower dissipation than the original (630mOhm). The Abracon AIAP-02-681K (1.61Ohm) produces substantially higher dissipation and requires thermal and circuit performance validation before implementation.

Q: Do all substitute parts maintain RoHS compliance?

A: Yes. Both substitute parts carry ROHS3 compliance certification, meeting current regulatory requirements. The original 18684C carries RoHS Compliant status, and both substitutes exceed this standard.

Q: How do operating temperature ranges affect part selection?

A: The original 18684C operates from 0°C to 70°C. The Bourns 5900-681-RC extends this to -55°C to 105°C, providing broader environmental compatibility. The Abracon AIAP-02-681K operates from -40°C to 85°C. Selection depends on application temperature requirements.

Q: What packaging considerations apply to these substitutes?

A: All three parts use through-hole axial packaging. The Bourns 5900-681-RC is supplied in trays (1439 units in stock), the Abracon AIAP-02-681K in bulk (745 units in stock), and the original Murata 18684C in standard packaging (761 units in stock). Packaging format may influence procurement and assembly processes.