MF-R300-0-99 Equivalent & Substitute Parts

Part Overview

The MF-R300-0-99 is a polymeric PTC resettable fuse manufactured by Bourns Inc., rated for 30V at 3A hold current with through-hole radial disc packaging. This component is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement continuity. Active alternatives from Bourns and other manufacturers provide identical electrical performance with current product availability.

Substiute Parts

MF-R300-0-99

Bourns Inc.In Stock: 1021MF-R300-0-99 Datasheet

Current PartRFQ

MF-R300

Bourns Inc.In Stock: 3130MF-R300 Datasheet

Parametric EquivalentRFQ

MF-R300-0-14

Bourns Inc.In Stock: 955MF-R300-0-14 Datasheet

Parametric EquivalentRFQ

FRU300-30F

RFE/FuzetecIn Stock: 1418FRU300-30F Datasheet

DirectRFQ

PTR030V0300-BK

Eaton - Electronics DivisionIn Stock: 841PTR030V0300-BK Datasheet

DirectRFQ

PFRA.300

SCHURTER Inc.In Stock: 747PFRA.300 Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the MF-R300-0-99 is determined by strict electrical and mechanical parameter matching:

Primary Substitution Criteria:

• Voltage - Max: 30V (exact match required)
• Current - Hold (Ih) (Max): 3 A (exact match required)
• Current - Trip (It): 6 A (exact match required)
• Time to Trip: 10.8 s (exact match required)
• Resistance - Initial (Ri) (Min): 20 mOhms (exact match required)
• Resistance - Post Trip (R1) (Max): 80 mOhms (exact match required)
• Operating Temperature: -40°C ~ 85°C (exact match required)
• Mounting Type: Through Hole (exact match required)
• Package / Case: Radial, Disc (exact match required)

Secondary Mechanical Considerations:

• Lead Spacing tolerance: 0.197" to 0.201" (5.00mm to 5.10mm) acceptable
• Physical dimensions: Minor variations in length and height permitted within standard PCB layout tolerances

All substitute parts listed meet these criteria and are confirmed as direct electrical and mechanical equivalents.

Parameter Comparison

Engineering Selection Recommendations

Bourns Inc. MF-R300 (Parametric Equivalent) Direct replacement from the original manufacturer. Identical electrical specifications and mechanical form factor. Active product status ensures long-term availability. Recommended as primary substitute for MF-R300-0-99.

Bourns Inc. MF-R300-0-14 (Parametric Equivalent) Functionally identical to MF-R300-0-99 with additional AEC-Q200 automotive qualification. Active product status. Expanded approval agency certifications (cUL, cURus, TUV, UL) provide enhanced compliance documentation. Suitable for applications requiring automotive-grade reliability.

RFE/Fuzetec FRU300-30F (Direct Manufacturer Equivalent) Meets all critical electrical parameters. Current - Max rating of 100A exceeds the 40A specification of the original part, providing additional design margin. Active product status. Mechanical dimensions vary slightly (11.40mm length vs. 12.00mm). Lead spacing matches at 0.201". Suitable for designs tolerating minor physical dimension variations.

Eaton PTR030V0300-BK (Direct Manufacturer Equivalent) Polymeric PTC resettable fuse with identical electrical performance. Active product status. Lead spacing of 0.197" (5.00mm) is within acceptable tolerance of the original 0.201" (5.10mm) specification. Physical dimensions slightly reduced (11.40mm length vs. 12.00mm). RoHS compliant. Suitable for space-constrained applications.

SCHURTER Inc. PFRA.300 (Parametric Equivalent) Meets all electrical and mechanical specifications. Active product status. Identical physical dimensions and lead spacing to MF-R300-0-99. ROHS3 compliant. Suitable for direct drop-in replacement in existing designs.

Frequently Asked Questions (FAQ)

Q: Can I use any of these substitute parts interchangeably with the MF-R300-0-99?

A: Yes. All listed substitute parts meet the identical electrical specifications (30V, 3A hold current, 6A trip current, 10.8s trip time, 20mOhms initial resistance, 80mOhms post-trip resistance) and operate across the same temperature range (-40°C to 85°C). All are through-hole radial disc packages with compatible lead spacing (0.197" to 0.201"). Mechanical dimensions vary slightly but remain within standard PCB layout tolerances.

Q: What is the difference between the Bourns MF-R300 and MF-R300-0-14?

A: Both are electrically and mechanically identical to the MF-R300-0-99. The MF-R300-0-14 carries AEC-Q200 automotive qualification and expanded approval agency certifications (cUL, cURus, TUV, UL vs. cURus, TUV). Select MF-R300-0-14 for applications requiring automotive-grade documentation or enhanced compliance verification.

Q: Why does the FRU300-30F have a higher Current - Max rating (100A vs. 40A)?

A: The Current - Max parameter represents the maximum current the fuse can interrupt. The FRU300-30F design permits higher interrupt capacity while maintaining identical hold current (3A) and trip current (6A) characteristics. This provides additional design margin without affecting normal circuit operation. The part remains a direct electrical equivalent for the MF-R300-0-99.

Q: Are there any lead spacing concerns when substituting parts?

A: Lead spacing varies minimally across substitutes: 0.201" (5.10mm) for MF-R300, MF-R300-0-14, FRU300-30F, and PFRA.300; 0.197" (5.00mm) for PTR030V0300-BK. These differences fall within standard PCB layout tolerances and do not require design modifications for through-hole radial disc mounting.

Q: Which substitute offers the best long-term availability?

A: All listed substitutes carry active product status. Bourns Inc. parts (MF-R300, MF-R300-0-14) represent the original manufacturer's current offerings and are recommended for designs prioritizing supply chain continuity with the original design source.

Q: Do all substitutes meet RoHS compliance?

A: Yes. All substitute parts are ROHS3 compliant or RoHS compliant, meeting current environmental and hazardous substance restrictions.