Littelfuse 0451001.MR Surface Mount Board Mount Fuse Equivalent & Substitute Parts

Part Overview

The Littelfuse 0451001.MR is a 1 A, 125 V AC/DC surface mount board mount fuse in the NANO²® 451 series, featuring a 2-SMD square end block package. This part is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement. Active alternatives from Littelfuse and cross-manufacturer options from Bourns provide direct functional equivalence while offering improved availability and compliance status.

Substiute Parts

0451001.MR

Littelfuse Inc.In Stock: 581900451001.MR Datasheet

Current PartRFQ

0448001.MR

Littelfuse Inc.In Stock: 202390448001.MR Datasheet

Parametric EquivalentRFQ

0451001.MRL

Littelfuse Inc.In Stock: 1802730451001.MRL Datasheet

Parametric EquivalentRFQ

0451001.MRSN

Littelfuse Inc.In Stock: 18100451001.MRSN Datasheet

Parametric EquivalentRFQ

0451001.NRL

LittelfuseIn Stock: 57640451001.NRL Datasheet

Parametric EquivalentRFQ

0453001.MR

Littelfuse Inc.In Stock: 211270453001.MR Datasheet

Parametric EquivalentRFQ

0453001.NR

Littelfuse Inc.In Stock: 12100453001.NR Datasheet

Parametric EquivalentRFQ

SF-2410FP100T-2

Bourns Inc.In Stock: 2299SF-2410FP100T-2 Datasheet

DirectRFQ

SF-2410HI100T-2

Bourns Inc.In Stock: 3688SF-2410HI100T-2 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 0451001.MR is determined by strict equivalence across the following parameters: current rating (1 A), AC voltage rating (125 V), DC voltage rating (125 V), response time (Fast Blow), mounting type (Surface Mount), fuse type (Board Mount), package configuration (2-SMD, Square End Block), breaking capacity (50 A), and operating temperature range (-55°C to 125°C).

All identified substitute parts meet these core electrical and mechanical requirements. Littelfuse parametric equivalents (0448001.MR, 0451001.MRL, 0451001.MRSN, 0451001.NRL, 0453001.MR, 0453001.NR) maintain identical or functionally equivalent specifications within the NANO²® series. Cross-manufacturer alternatives from Bourns (SF-2410FP100T-2, SF-2410HI100T-2) provide equivalent electrical performance and package compatibility. Variations in melting I²t, DC cold resistance, and packaging format (Cut Tape, Tape & Reel) do not affect functional substitution but may influence procurement and assembly considerations.

Parameter Comparison

Engineering Selection Recommendations

For applications requiring direct replacement of the obsolete 0451001.MR, the Littelfuse 0451001.MRL offers identical electrical specifications and series continuity with active product status and ROHS3 compliance. This part is available in Cut Tape and Digi-Reel® packaging formats with substantial inventory (180,200 pcs).

The Littelfuse 0448001.MR provides an alternative within the NANO²® family with active status and ROHS3 compliance. While melting I²t and DC cold resistance differ slightly (0.441 vs. 0.459, and 0.0863 vs. 0.153 Ω respectively), these variations remain within functional equivalence for the specified 1 A, 125 V AC/DC application.

For cross-manufacturer substitution, the Bourns SF-2410FP100T-2 and SF-2410HI100T-2 deliver equivalent electrical performance with active product status and ROHS3 compliance. The SF-2410FP100T-2 maintains closer melting I²t alignment (0.4143), while the SF-2410HI100T-2 exhibits higher melting I²t (1.9933) suitable for applications requiring slower response characteristics within the fast-blow category.

All substitute parts carry UL and CSA certifications consistent with the original part's approval agencies, ensuring regulatory compliance for end applications.

Frequently Asked Questions (FAQ)

Q: Can the 0451001.MRL directly replace the obsolete 0451001.MR?

A: Yes. The 0451001.MRL maintains identical electrical specifications (1 A, 125 V AC/DC, Fast Blow, 50 A breaking capacity) and mechanical package (2-SMD, Square End Block). The primary difference is product status (Active vs. Obsolete) and RoHS compliance (ROHS3 vs. non-compliant). Packaging options differ (Cut Tape & Digi-Reel® vs. standard format), but electrical and mechanical compatibility is complete.

Q: What is the functional difference between the Littelfuse NANO²® 448, 451, and 453 series?

A: All three series (0448001.MR, 0451001.MRL, 0453001.MR) meet the core electrical requirements of 1 A, 125 V AC/DC operation with identical breaking capacity and package configuration. Series designation reflects internal design evolution within Littelfuse's product line. Melting I²t and DC cold resistance specifications remain consistent across 451 and 453 variants, while the 448 series exhibits lower DC cold resistance (0.0863 Ω). For the specified application, all three are functionally equivalent.

Q: How do the Bourns SinglFuse™ parts compare to Littelfuse NANO²® equivalents?

A: The Bourns SF-2410FP100T-2 and SF-2410HI100T-2 deliver equivalent electrical performance (1 A, 125 V AC/DC, 50 A breaking capacity) and identical package configuration (2-SMD, Square End Block). Physical dimensions vary slightly (0.102" vs. 0.106" width and height), remaining within standard PCB footprint tolerances. The primary distinction is melting I²t: SF-2410FP100T-2 (0.4143) aligns closely with Littelfuse fast-blow characteristics, while SF-2410HI100T-2 (1.9933) provides extended response time within the fast-blow classification. Both carry UL and cUL certifications.

Q: Does packaging format (Cut Tape, Digi-Reel®, Tape & Reel) affect electrical or mechanical compatibility?

A: No. Packaging format affects procurement, storage, and assembly logistics only. Electrical specifications, mechanical dimensions, and functional performance remain identical across all packaging options for a given part number. Selection should be based on assembly equipment compatibility and inventory management requirements.

Q: Are all substitute parts RoHS3 compliant?

A: All identified substitute parts carry ROHS3 Compliant status. The original 0451001.MR is RoHS non-compliant. For applications subject to RoHS regulations, any active substitute part listed provides compliant replacement.

Q: Which substitute part offers the best availability?

A: The Littelfuse 0451001.MRL provides the highest inventory level (180,200 pcs), followed by 0451001.MRSN (1,766 pcs) and 0451001.NRL (5,742 pcs). All three maintain identical electrical specifications to the original part. Bourns alternatives (SF-2410FP100T-2: 2,251 pcs; SF-2410HI100T-2: 3,596 pcs) offer cross-manufacturer options with comparable availability.