Littelfuse 0451.160MRSN Surface Mount Board Fuse - Equivalent & Substitute Parts

Part Overview

The Littelfuse 0451.160MRSN is a 160 mA, 125 V AC surface mount board fuse in the NANO²® 451 series. This fast-blow fuse is designed for board-level circuit protection in applications requiring compact, high-density mounting. The part is actively manufactured and stocked, with full compliance to RoHS3 and international safety standards (CSA, UR). Substitute parts are identified to provide design flexibility, inventory alternatives, and continuity of supply across the NANO²® fuse product family.

Substiute Parts

0451.160MRSN

Littelfuse Inc.In Stock: 9940451.160MRSN Datasheet

Current PartRFQ

0448.160MR

Littelfuse Inc.In Stock: 74050448.160MR Datasheet

Parametric EquivalentRFQ

0451.160MRL

LittelfuseIn Stock: 54700451.160MRL Datasheet

Parametric EquivalentRFQ

0453.160MR

Littelfuse Inc.In Stock: 20850453.160MR Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 0451.160MRSN are qualified based on the following critical parameters that must remain constant:

• Current Rating: 160 mA (exact match required)
• Voltage Rating (AC): 125 V (exact match required)
• Mounting Type: Surface Mount (exact match required)
• Package / Case: 2-SMD, Square End Block (exact match required)
• Size / Dimension: 0.240" L x 0.106" W x 0.106" H (exact match required)
• Response Time: Fast Blow (exact match required)
• Breaking Capacity @ Rated Voltage: 50A (exact match required)
• Operating Temperature Range: -55°C ~ 125°C (exact match required)
• Approval Agencies: CSA and/or UL/UR (equivalent certifications acceptable)
• RoHS Status: ROHS3 Compliant (exact match required)

The following substitute parts meet all critical substitution criteria:

1. 0448.160MR (NANO²® 448 series) - Parametric equivalent with DC voltage rating specified
2. 0451.160MRL (NANO²® 451 series) - Same series variant with DC voltage rating specified
3. 0453.160MR (NANO²® 453 series) - Alternative series with equivalent electrical characteristics

Parameter Comparison

Engineering Selection Recommendations

All substitute parts are actively manufactured and fully compliant with RoHS3 and international safety certifications. Selection among the qualified substitutes should be based on the following factors:

0451.160MRL - Recommended as primary substitute. Identical series (NANO²® 451), matching electrical characteristics (Melting I²t: 0.0048, DC Cold Resistance: 1.2157 Ohms), and equivalent certifications (CSA, UL). Highest compatibility with original design intent.

0453.160MR - Acceptable substitute. NANO²® 453 series with identical electrical characteristics (Melting I²t: 0.0048, DC Cold Resistance: 1.2157 Ohms) and equivalent certifications (CSA, UL). Suitable for applications requiring alternative series sourcing.

0448.160MR - Acceptable substitute with design consideration. NANO²® 448 series with different thermal characteristics (Melting I²t: 0.0028, DC Cold Resistance: 1.76 Ohms). Highest inventory availability (7300 Pcs). Use only when thermal response differences are acceptable to circuit design.

All substitutes maintain identical physical dimensions, mounting footprint, current rating, AC voltage rating, and breaking capacity, ensuring direct board-level compatibility.

Frequently Asked Questions (FAQ)

Q: Can I use 0448.160MR as a direct replacement for 0451.160MRSN?

A: Yes, 0448.160MR is electrically and mechanically compatible. However, it has different thermal characteristics (lower Melting I²t: 0.0028 vs. 0.0048, higher DC Cold Resistance: 1.76 vs. 1.2157 Ohms). Use only if your circuit design accommodates these thermal differences.

Q: What is the difference between 0451.160MRSN and 0451.160MRL?

A: Both are NANO²® 451 series fuses with identical electrical and thermal characteristics. The primary difference is that 0451.160MRL explicitly specifies DC voltage rating (125 V DC), while 0451.160MRSN does not. They are mechanically and electrically interchangeable.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. All listed substitute parts (0448.160MR, 0451.160MRL, 0453.160MR) are ROHS3 Compliant.

Q: Do all substitute parts have the same physical dimensions?

A: Yes. All substitute parts share identical dimensions: 0.240" L x 0.106" W x 0.106" H (6.10mm x 2.69mm x 2.69mm), ensuring identical PCB footprint and mounting compatibility.

Q: Which substitute has the best inventory availability?

A: 0448.160MR has the highest inventory stock at 7300 Pcs, compared to 5400 Pcs for 0451.160MRL and 1992 Pcs for 0453.160MR.

Q: Are the approval certifications equivalent across all substitutes?

A: All substitutes carry CSA certification. The original part (0451.160MRSN) and 0448.160MR carry UR certification, while 0451.160MRL and 0453.160MR carry UL certification. UL and UR are equivalent for this product category.

Q: Can I mix different substitute parts in the same production run?

A: Yes, all substitute parts meet identical electrical and mechanical specifications for the 160 mA, 125 V AC fast-blow fuse category. However, if thermal response characteristics are critical to your circuit design, maintain consistency within a production batch.