Littelfuse 044102.5WRA Surface Mount Fuse Equivalent & Substitute Parts

Part Overview

The Littelfuse 044102.5WRA is a 2.5 A fast-blow surface mount fuse rated for 32 V DC operation in 0603 (1608 Metric) package format. This board mount fuse is designed for circuit protection in compact electronic assemblies requiring reliable overcurrent protection. The part is currently in active production status with CE and cURus certifications. Equivalent and substitute parts are identified for applications where alternative sourcing, packaging formats, or voltage rating combinations are required.

Substiute Parts

044102.5WRA

Littelfuse Inc.In Stock: 3813044102.5WRA Datasheet

Current PartRFQ

043802.5WR

Littelfuse Inc.In Stock: 4138043802.5WR Datasheet

Parametric EquivalentRFQ

043802.5WRGT

Littelfuse Inc.In Stock: 17312043802.5WRGT Datasheet

Parametric EquivalentRFQ

044102.5WR

Littelfuse Inc.In Stock: 4389044102.5WR Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 044102.5WRA are identified based on the following critical parameters that determine functional equivalence:

Primary Matching Criteria:

• Current Rating: 2.5 A (exact match required)
• Package / Case: 0603 (1608 Metric) (exact match required)
• Mounting Type: Surface Mount (exact match required)
• Fuse Type: Board Mount (Cartridge Style Excluded) (exact match required)
• Response Time: Fast Blow (exact match required)
• Voltage Rating - DC: 32 V (exact match required)
• Operating Temperature Range: -55°C to 150°C (exact match required)

Secondary Considerations:

• Packaging format (Tape & Reel vs. bulk)
• Product status (Active vs. Obsolete)
• Approval agency certifications
• Melting I²t characteristics
• DC Cold Resistance values

The substitute parts listed maintain identical electrical and mechanical specifications for the primary matching criteria, ensuring direct functional replacement in circuit protection applications.

Parameter Comparison

Engineering Selection Recommendations

044102.5WR is the primary direct substitute for 044102.5WRA. Both parts share identical electrical characteristics (2.5 A, 32 V DC, 0.552 Melting I²t, 0.02 Ohms DC Cold Resistance) and are in active production status. The primary difference is approval agency certification: 044102.5WRA carries CE and cURus approvals, while 044102.5WR carries CSA and UL approvals. Selection between these two should be based on regional compliance requirements and certification mandates for the target application.

043802.5WRGT is an active substitute with identical current rating, voltage rating, and package specifications. This part carries CSA and cURus certifications and is available in Tape & Reel packaging with higher inventory availability (17,281 pcs). The Melting I²t value (0.24) differs from the main part (0.552), indicating different thermal response characteristics. This part includes AC voltage rating (12 V AC) in addition to DC rating, providing broader application flexibility.

043802.5WR is an obsolete substitute part. Although it meets all primary electrical and mechanical matching criteria, its obsolete status makes it unsuitable for new designs or long-term production applications. This part should only be considered for legacy system maintenance or repair applications where original part specifications are mandatory.

Frequently Asked Questions (FAQ)

Q: Can 044102.5WR be used as a direct replacement for 044102.5WRA?

A: Yes. Both parts are electrically and mechanically identical with matching current ratings (2.5 A), voltage ratings (32 V DC), response time (Fast Blow), package format (0603), and thermal characteristics (0.552 Melting I²t, 0.02 Ohms DC Cold Resistance). Selection should be based on regional certification requirements: 044102.5WRA requires CE and cURus approvals, while 044102.5WR requires CSA and UL approvals.

Q: What is the difference between 043802.5WRGT and 044102.5WRA?

A: Both parts share identical current rating (2.5 A), DC voltage rating (32 V), response time (Fast Blow), and package format (0603). The primary differences are: 043802.5WRGT includes AC voltage rating (12 V AC) capability, has a lower Melting I²t value (0.24 vs. 0.552), carries different certifications (CSA, cURus vs. CE, cURus), and is in active production with higher inventory availability. The lower Melting I²t indicates faster thermal response.

Q: Why is 043802.5WR listed as obsolete?

A: 043802.5WR is marked as obsolete by the manufacturer. Although it meets all electrical and mechanical specifications for substitution, its discontinued production status makes it unsuitable for new designs. This part should only be used for legacy system maintenance where original specifications are required.

Q: Are all substitute parts available in Tape & Reel packaging?

A: 044102.5WRA, 043802.5WRGT, and 044102.5WR are all available in Tape & Reel (TR) packaging. 043802.5WR packaging format is not specified in available documentation.

Q: Do all substitute parts meet RoHS compliance?

A: Yes. All listed parts (044102.5WRA, 043802.5WR, 043802.5WRGT, and 044102.5WR) are ROHS3 Compliant and REACH Unaffected.

Q: What is the significance of the Melting I²t value difference between parts?

A: Melting I²t characterizes the thermal energy required to melt the fuse element. 044102.5WRA and 044102.5WR both have 0.552 Melting I²t, while 043802.5WRGT has 0.24 Melting I²t. The lower value in 043802.5WRGT indicates faster thermal response to overcurrent conditions. Selection should be based on circuit protection timing requirements.

Q: Which substitute part has the best availability?

A: 043802.5WRGT has the highest inventory availability at 17,281 pcs in stock, compared to 044102.5WRA (3,705 pcs), 044102.5WR (4,282 pcs), and 043802.5WR (4,124 pcs).