Murata Power Solutions 49681SC Equivalent & Substitute Parts

Part Overview

The Murata Power Solutions 49681SC is a 680 µH shielded wirewound inductor rated for 620 mA continuous current with a maximum DC resistance of 1.2Ohm. This surface mount component operates across the temperature range of -40°C to 85°C and is designed for applications requiring compact, shielded inductive filtering and energy storage in power conversion circuits. The part is currently active in production with full RoHS3 compliance and unlimited moisture sensitivity rating. Substitute parts are identified when equivalent inductance values, current ratings, and shielding characteristics align within acceptable electrical and mechanical tolerances for the intended application.

Substiute Parts

49681SC

Murata Power Solutions Inc.In Stock: 78049681SC Datasheet

Current PartRFQ

SRR1280-681K

Bourns Inc.In Stock: 1772SRR1280-681K Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

The Bourns Inc. SRR1280-681K qualifies as a direct substitute based on the following alignment of critical electrical parameters:

Inductance Match: Both parts specify 680 µH inductance value, meeting the primary functional requirement.

Current Rating Compatibility: The substitute part provides 750 mA continuous current rating, which exceeds the main part's 620 mA specification. This higher rating ensures the substitute can handle the intended application load without derating.

DC Resistance Tolerance: The substitute's 1.3Ohm maximum DCR is within acceptable variance from the main part's 1.2Ohm specification. Both values fall within typical design margins for power conversion applications.

Shielding Characteristic: Both parts feature shielded construction, maintaining electromagnetic isolation requirements.

Surface Mount Compatibility: Both components are surface mount devices with nonstandard 4-lead packages and identical seated height of 0.315" (8.00mm), ensuring mechanical compatibility in existing PCB layouts.

Compliance Alignment: Both parts carry ROHS3 compliance and unlimited moisture sensitivity rating (MSL 1), meeting regulatory and environmental requirements.

Parameter Comparison

Engineering Selection Recommendations

Both the Murata 49681SC and Bourns SRR1280-681K are active production components with full ROHS3 compliance and unlimited moisture sensitivity ratings. The Bourns substitute provides enhanced specifications in three areas: higher current rating (750 mA vs. 620 mA), tighter inductance tolerance (±10% vs. ±20%), and extended operating temperature range (-40°C to 125°C vs. -40°C to 85°C). The substitute's slightly higher DCR (1.3Ohm vs. 1.2Ohm) and marginally larger footprint (12.50mm vs. 12.20mm) represent minor trade-offs offset by improved current headroom and temperature performance. Selection between these parts depends on application-specific requirements for current margin, temperature environment, and tolerance specifications.

Frequently Asked Questions (FAQ)

Q: Can the Bourns SRR1280-681K directly replace the Murata 49681SC in existing designs?

A: Yes, provided PCB layout accommodates the slightly larger footprint (12.50mm vs. 12.20mm). Both parts share identical seated height (8.00mm), 4-lead nonstandard packages, and surface mount compatibility. Electrical parameters align within acceptable design margins.

Q: What is the significance of the inductance tolerance difference (±20% vs. ±10%)?

A: The Bourns substitute offers tighter inductance tolerance, reducing variation in the final inductance value. Applications requiring precise inductance specifications benefit from the ±10% tolerance of the substitute part.

Q: Does the higher current rating of the substitute part affect circuit performance?

A: The higher current rating (750 mA vs. 620 mA) provides additional design margin and reduces thermal stress on the component. It does not negatively affect circuit performance when the original design current requirement is 620 mA or less.

Q: Are there mechanical compatibility concerns with the footprint difference?

A: The footprint difference is minimal (0.3mm in length and width). Standard PCB design practices accommodate this variation. Verify pad spacing and clearance in your specific layout before implementation.

Q: Do both parts meet the same regulatory and environmental standards?

A: Yes. Both the Murata 49681SC and Bourns SRR1280-681K carry ROHS3 compliance, REACH unaffected status, and unlimited moisture sensitivity rating (MSL 1), meeting identical regulatory requirements.

Q: What is the impact of the extended temperature range in the substitute part?

A: The Bourns substitute operates to 125°C versus 85°C for the Murata part. This extended range provides additional thermal margin for applications in elevated ambient or high-power environments, though it does not affect performance in standard operating conditions.