Littelfuse 0263.125M Fuse - Equivalent & Substitute Parts

Part Overview

The Littelfuse 0263.125M is a 125 mA, 250 V AC/DC board mount axial fuse with fast blow response characteristics. This component is classified as obsolete, which necessitates identification of active equivalent parts for ongoing design support and procurement. The PICO® II 263 series fuse is designed for through-hole axial mounting applications requiring reliable overcurrent protection in industrial and commercial electronics.

Substiute Parts

0263.125M

Littelfuse Inc.In Stock: 10150263.125M Datasheet

Current PartRFQ

0263.125MXL

Littelfuse Inc.In Stock: 70270263.125MXL Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the obsolete 0263.125M is based on electrical and mechanical parameter equivalence within the PICO® II 263 series. The substitute part 0263.125MXL maintains identical specifications across all critical parameters: current rating (125 mA), voltage rating (250 V AC), response time (fast blow), breaking capacity (50 A), melting I²t (0.00251), operating temperature range (-55°C to 125°C), DC cold resistance (1.75 Ohms), and physical dimensions (0.155" Dia x 0.280" L).

The key substitution criteria are:

• Current Rating: 125 mA (exact match)
• Voltage Rating: 250 V AC (exact match)
• Response Characteristic: Fast Blow (exact match)
• Physical Dimensions: 0.155" Dia x 0.280" L (exact match)
• Thermal Characteristics: Melting I²t 0.00251 (exact match)

Parameter Comparison

Engineering Selection Recommendations

The 0263.125MXL is the direct active equivalent for the obsolete 0263.125M. Both parts are manufactured by Littelfuse Inc. within the PICO® II 263 series and share identical electrical and mechanical specifications. The primary distinction is product status and regulatory compliance: the 0263.125MXL is active in production and ROHS3 compliant, whereas the 0263.125M is obsolete and RoHS non-compliant.

For new designs or component replacement in existing applications, the 0263.125MXL is the appropriate selection. The part maintains full electrical equivalence, identical thermal characteristics, and equivalent mechanical fit for through-hole axial mounting. Both parts carry CSA and UR approvals, confirming suitability for regulated applications.

Frequently Asked Questions (FAQ)

Q: Can the 0263.125MXL be used as a direct replacement for the 0263.125M?

A: Yes. The 0263.125MXL is electrically and mechanically identical to the 0263.125M. Both parts have the same current rating (125 mA), voltage rating (250 V AC), response time (fast blow), physical dimensions (0.155" Dia x 0.280" L), and thermal characteristics (melting I²t 0.00251). The parts are pin-compatible for through-hole axial mounting applications.

Q: What is the difference between these two part numbers?

A: The primary differences are product status and regulatory compliance. The 0263.125M is obsolete and RoHS non-compliant. The 0263.125MXL is an active production part that is ROHS3 compliant. All electrical and mechanical parameters are identical.

Q: Are there any packaging differences between 0263.125M and 0263.125MXL?

A: The 0263.125M was supplied in standard packaging, while the 0263.125MXL is supplied in bulk packaging. Both parts use the same axial package / case format and are suitable for the same PCB mounting applications.

Q: What certifications apply to both parts?

A: Both the 0263.125M and 0263.125MXL carry CSA and UR approvals, confirming compliance with recognized safety standards for overcurrent protection devices.

Q: Is the 0263.125MXL suitable for applications requiring RoHS compliance?

A: Yes. The 0263.125MXL is ROHS3 compliant and REACH unaffected, making it suitable for applications with RoHS regulatory requirements. The obsolete 0263.125M does not meet these compliance standards.