MF-USML250-2 Equivalent & Substitute Parts

Part Overview

The MF-USML250-2 is a Polymeric PTC Resettable Fuse manufactured by Bourns Inc., rated for 6V maximum voltage with a 2.5A hold current. This component is classified as Obsolete, making identification of compatible substitute parts essential for ongoing design support and procurement continuity. The Multifuse® series provides automatic overcurrent protection through polymeric positive temperature coefficient technology, resetting after fault conditions are cleared.

Substiute Parts

MF-USML250-2

Bourns Inc.In Stock: 663MF-USML250-2 Datasheet

Current PartRFQ

MF-USML260/6-2

Bourns Inc.In Stock: 1205MF-USML260/6-2 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the MF-USML250-2 is determined by strict electrical and mechanical compatibility within the Multifuse® PTC resettable fuse category. The primary substitute identified is the MF-USML260/6-2, which maintains compatibility through the following critical parameters:

Substitution Criteria:

• Identical maximum voltage rating (6V)
• Identical mounting type and package footprint (1210 / 3225 Metric, Concave, Surface Mount)
• Identical physical dimensions (0.127" L x 0.101" W)
• Identical operating temperature range (-40°C ~ 85°C)
• Identical approval agencies (cURus, TUV)
• Identical RoHS and REACH compliance status
• Identical MSL rating (2A, 4 Weeks)

The MF-USML260/6-2 differs in hold current (2.6A vs. 2.5A), trip current (5.2A vs. 5A), and post-trip resistance characteristics, but these variations remain within the allowable substitution parameters for this product category.

Parameter Comparison

Engineering Selection Recommendations

The MF-USML260/6-2 is the qualified substitute for the obsolete MF-USML250-2. Selection is based on the following engineering factors:

Product Status: The MF-USML260/6-2 maintains Active product status, ensuring continued manufacturer support, availability, and compliance updates. The MF-USML250-2 is classified as Obsolete, necessitating transition to an active equivalent.

Regulatory Compliance: Both components carry identical certifications (cURus, TUV), ROHS3 compliance, and REACH unaffected status, confirming equivalent regulatory standing for applications requiring these certifications.

Mechanical Compatibility: Identical package footprint (1210 / 3225 Metric, Concave) and surface mount configuration ensure direct PCB layout compatibility without redesign.

Electrical Parameters: The substitute maintains the 6V maximum voltage rating and 50A maximum current rating. The 0.1A increase in hold current (2.5A to 2.6A) and 0.2A increase in trip current (5A to 5.2A) represent proportional adjustments within the Multifuse® series design envelope.

Frequently Asked Questions (FAQ)

Q: Can the MF-USML260/6-2 be used as a direct replacement for the MF-USML250-2 on existing PCBs?

A: Yes. Both components share identical package geometry (1210 / 3225 Metric, Concave), surface mount configuration, and physical dimensions (0.127" L x 0.101-0.102" W). PCB footprints designed for the MF-USML250-2 accommodate the MF-USML260/6-2 without modification.

Q: What are the key electrical differences between these two parts?

A: The MF-USML260/6-2 has a slightly higher hold current (2.6A vs. 2.5A) and trip current (5.2A vs. 5.2A), with extended time-to-trip (5s vs. 4.6s) and increased post-trip resistance (30 mOhms vs. 22 mOhms). Both maintain the 6V voltage rating and 50A maximum current specification.

Q: Are there any compliance or certification differences?

A: No. Both components carry identical approvals (cURus, TUV), ROHS3 compliance, REACH unaffected status, and identical MSL ratings (2A, 4 Weeks). Regulatory standing is equivalent.

Q: Why is the MF-USML250-2 listed as Obsolete?

A: Obsolete status indicates the manufacturer has discontinued active production and support. The MF-USML260/6-2 is the active equivalent within the Multifuse® series, ensuring continued availability and compliance support.

Q: What is the thickness difference, and does it affect PCB assembly?

A: The MF-USML260/6-2 has a maximum thickness of 0.031" (0.80mm) compared to 0.024" (0.60mm) for the MF-USML250-2. This 0.007" difference is within standard PCB assembly tolerances and does not affect reflow soldering or component placement processes.

Q: Are there other substitutes available for the MF-USML250-2?

A: Based on the provided data, the MF-USML260/6-2 is the identified substitute. Additional cross-references for the MF-USML260/6-2 include PTSLR12106V260 and MF-USML260/12-2, which represent alternative packaging or series variants within the Bourns Multifuse® portfolio.