72R025XU Polymeric PTC Resettable Fuse - Equivalent & Substitute Parts

Part Overview

The 72R025XU is a polymeric PTC resettable fuse manufactured by Littelfuse Inc. in the POLY-FUSE® 72R series. This component is rated for 72V maximum voltage with a 250 mA hold current and 500 mA trip current, designed for through-hole radial mounting in disc configuration. The 72R025XU has reached obsolete product status, making identification of equivalent substitute parts essential for ongoing design support and component procurement.

Substiute Parts

72R025XU

Littelfuse Inc.In Stock: 93072R025XU Datasheet

Current PartRFQ

RXEF025

Littelfuse Inc.In Stock: 34164RXEF025 Datasheet

MFR RecommendedRFQ

MF-RX025/72-0

Bourns Inc.In Stock: 2601MF-RX025/72-0 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 72R025XU is determined by strict equivalence across the following critical parameters:

• Voltage rating: 72V maximum
• Hold current: 250 mA
• Trip current: 500 mA
• Mounting configuration: Through hole radial disc
• Physical dimensions and lead spacing compatibility
• Operating temperature range: -40°C to 85°C
• Resistance characteristics: Initial and post-trip values

The substitute parts RXEF025 and MF-RX025/72-0 maintain these core electrical and mechanical specifications, enabling direct functional replacement in circuit applications designed for the 72R025XU.

Parameter Comparison

Engineering Selection Recommendations

Both RXEF025 and MF-RX025/72-0 are active production parts suitable for replacing the obsolete 72R025XU. Selection between these substitutes should be based on the following factors:

RXEF025 (Littelfuse PolySwitch® RXEF series) maintains identical electrical specifications and physical dimensions to the original 72R025XU. This part carries expanded regulatory approvals including CQC, CSA, TUV, and UL certifications, providing broader compliance coverage for international applications.

MF-RX025/72-0 (Bourns Multifuse® MF-RX/72 series) provides equivalent electrical performance with identical physical dimensions and lead spacing to the original part. Initial resistance is specified at 1 Ohm minimum, compared to 1.25 Ohms for the 72R025XU and RXEF025. This part carries REACH Unaffected status and maintains cURus and TUV approvals.

Both parts are ROHS3 compliant with unlimited moisture sensitivity level (MSL 1) and are suitable for direct PCB mounting in applications originally designed for the 72R025XU.

Frequently Asked Questions (FAQ)

Q: Can RXEF025 and MF-RX025/72-0 be used interchangeably with 72R025XU?

A: Both parts meet the core electrical and mechanical specifications of the 72R025XU. Physical dimensions are compatible with existing PCB layouts. Minor variations in lead spacing (0.199" to 0.201") and thickness (0.118" to 0.122") fall within standard through-hole mounting tolerances.

Q: What is the difference in initial resistance between the substitute parts?

A: The 72R025XU and RXEF025 specify minimum initial resistance of 1.25 Ohms. The MF-RX025/72-0 specifies 1 Ohm minimum. All three parts maintain maximum post-trip resistance of 3 Ohms. This difference does not affect substitution compatibility for standard circuit protection applications.

Q: Are there packaging differences between the substitute parts?

A: RXEF025 is supplied in bag packaging, while MF-RX025/72-0 is supplied in bulk packaging. The 72R025XU was supplied in standard packaging. Packaging format does not affect component performance or PCB mounting.

Q: Which substitute part has broader regulatory approval?

A: RXEF025 carries CQC, CSA, TUV, and UL approvals. MF-RX025/72-0 carries cURus and TUV approvals. Selection should align with specific regulatory requirements for the target application and geographic market.

Q: Are both substitute parts currently in production?

A: Both RXEF025 and MF-RX025/72-0 are active production parts with current inventory availability, unlike the obsolete 72R025XU.