Littelfuse 0251.630MAT1 Board Mount Fuse Equivalent & Substitute Parts

Part Overview

The Littelfuse 0251.630MAT1 is a 630 mA, 125 V AC/DC board mount fuse in axial package configuration, part of the PICO® II 251 series. This component is classified as obsolete, which necessitates identification of active equivalent alternatives for new designs and ongoing production requirements. Substitute parts maintain identical electrical and mechanical specifications while offering improved product status and compliance certifications.

Substiute Parts

0251.630MAT1

Littelfuse Inc.In Stock: 11000251.630MAT1 Datasheet

Current PartRFQ

0251.630MAT1L

Littelfuse Inc.In Stock: 10670251.630MAT1L Datasheet

DirectRFQ

0251.630NAT1L

Littelfuse Inc.In Stock: 9920251.630NAT1L Datasheet

Parametric EquivalentRFQ

0251.630PAT1L

Littelfuse Inc.In Stock: 7600251.630PAT1L Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the 0251.630MAT1 are qualified based on strict parametric equivalence across all electrical and mechanical specifications. The substitution logic is determined by the following criteria:

Electrical Parameters (Must Match Exactly):

• Current Rating: 630 mA
• Voltage Rating AC: 125 V
• Voltage Rating DC: 125 V
• Response Time: Fast Blow
• Breaking Capacity @ Rated Voltage: 50A AC, 300A DC
• Melting I²t: 0.08
• DC Cold Resistance: 0.205 Ohms

Mechanical Parameters (Must Match Exactly):

• Mounting Type: Through Hole
• Package / Case: Axial
• Size / Dimension: 0.110" Dia x 0.280" L (2.80mm x 7.11mm)

Certification & Compliance (Must Match):

• Approval Agencies: CSA, cURus
• Operating Temperature Range: -55°C to 125°C

All three substitute parts (0251.630MAT1L, 0251.630NAT1L, 0251.630PAT1L) meet these criteria and differ only in packaging format and product status.

Parameter Comparison

Engineering Selection Recommendations

All three substitute parts are direct parametric equivalents to the 0251.630MAT1 and are suitable for replacement in applications requiring 630 mA, 125 V AC/DC board mount fuses with fast blow response characteristics.

Product Status Consideration: The main part (0251.630MAT1) is obsolete. All substitute parts (0251.630MAT1L, 0251.630NAT1L, 0251.630PAT1L) maintain active product status, ensuring long-term availability and supply chain continuity.

Compliance Advantage: All substitute parts are ROHS3 compliant and REACH unaffected, compared to the non-compliant status of the original part. This compliance improvement is significant for applications subject to environmental regulations.

Packaging Selection: Choice among the three active substitutes depends on procurement and assembly requirements:

• 0251.630MAT1L: Cut Tape (CT) packaging for automated pick-and-place assembly
• 0251.630NAT1L: Tape & Box (TB) packaging for standard reel-based handling
• 0251.630PAT1L: Tape & Box (TB) packaging for standard reel-based handling

Frequently Asked Questions (FAQ)

Q: Can 0251.630MAT1L, 0251.630NAT1L, and 0251.630PAT1L be used interchangeably with 0251.630MAT1?

A: Yes. All three parts are parametric equivalents with identical electrical and mechanical specifications. They differ only in packaging format and product status. The obsolete 0251.630MAT1 can be directly replaced by any of the three active alternatives without circuit modification.

Q: What is the difference between the three substitute parts?

A: The three substitute parts are electrically and mechanically identical. The differences are:

• 0251.630MAT1L uses Cut Tape (CT) packaging, suitable for automated assembly lines
• 0251.630NAT1L uses Tape & Box (TB) packaging for standard handling
• 0251.630PAT1L uses Tape & Box (TB) packaging for standard handling

Selection depends on assembly process requirements and procurement preferences.

Q: Why should I use a substitute part instead of the original 0251.630MAT1?

A: The original part is obsolete, creating supply chain risk. All substitute parts are active products with confirmed availability. Additionally, substitute parts are ROHS3 compliant, meeting current environmental regulations, whereas the original part is non-compliant.

Q: Are the physical dimensions identical across all parts?

A: Yes. All parts, including the main part and substitutes, share identical dimensions of 0.110" Dia x 0.280" L (2.80mm x 7.11mm) in axial package configuration. They are mechanically interchangeable on PCBs designed for the original part.

Q: Do all parts carry the same certifications?

A: Yes. All parts carry CSA and cURus approvals and operate across the same temperature range (-55°C to 125°C). The substitute parts additionally meet ROHS3 compliance and REACH unaffected status.

Q: Which substitute part should I choose for new designs?

A: For new designs, any of the three active substitutes is acceptable. Selection should be based on your assembly process: use Cut Tape (CT) for automated assembly, or Tape & Box (TB) for manual or semi-automated processes.