Littelfuse 0263.250M Equivalent & Substitute Parts

Part Overview

The Littelfuse 0263.250M is a 250 mA, 250 V AC/DC board mount axial fuse from the PICO® II 263 series. This component is classified as obsolete, making identification of suitable substitutes essential for ongoing system support and component procurement. The part is designed for through-hole mounting applications requiring fast-blow protection characteristics in compact axial packaging.

Substiute Parts

0263.250M

Littelfuse Inc.In Stock: 8360263.250M Datasheet

Current PartRFQ

0263.250MXL

Littelfuse Inc.In Stock: 11930263.250MXL Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the 0263.250M is determined by strict equivalence across the following critical parameters:

• Current Rating: 250 mA (exact match required)
• Voltage Rating: 250 V AC (exact match required)
• Response Time: Fast Blow (exact match required)
• Mounting Type: Through Hole (exact match required)
• Package Style: Axial (exact match required)
• Breaking Capacity: 50 A @ rated voltage (exact match required)
• Melting I²t: 0.0165 (exact match required)
• Thermal Operating Range: -55°C to 125°C (exact match required)
• DC Cold Resistance: 0.715 Ohms (exact match required)

The substitute part 0263.250MXL meets all electrical and mechanical parameters identically to the main part, differing only in product status and compliance certifications.

Parameter Comparison

Engineering Selection Recommendations

The 0263.250MXL is the direct substitute for the obsolete 0263.250M. Both parts are manufactured by Littelfuse Inc. within the PICO® II 263 series and maintain identical electrical and mechanical specifications. The primary distinction is product lifecycle status: the 0263.250M is obsolete, while the 0263.250MXL is active and available.

The 0263.250MXL offers improved compliance posture, meeting ROHS3 requirements and REACH unaffected status, compared to the non-compliant status of the original part. Both parts carry CSA and UR approvals, confirming regulatory acceptance for their intended applications.

For new designs or component replenishment, the 0263.250MXL is the appropriate selection. For legacy system maintenance requiring exact historical equivalence, the 0263.250M and 0263.250MXL are functionally and mechanically interchangeable.

Frequently Asked Questions (FAQ)

Q: Can the 0263.250MXL be used as a direct replacement for the 0263.250M?

A: Yes. Both parts are electrically and mechanically identical across all specified parameters, including current rating, voltage rating, response time, package dimensions, and thermal operating range. The 0263.250MXL is the active production equivalent.

Q: What is the difference between the 0263.250M and 0263.250MXL?

A: The parts are functionally equivalent. The 0263.250M is obsolete, while the 0263.250MXL is active. The 0263.250MXL meets ROHS3 compliance and REACH unaffected status, whereas the 0263.250M is RoHS non-compliant.

Q: Are there any dimensional or mounting differences between these parts?

A: No. Both parts share identical dimensions (0.155" Dia × 0.280" L) and through-hole axial mounting configuration. PCB layout and footprint requirements are unchanged.

Q: Do both parts carry the same regulatory approvals?

A: Yes. Both the 0263.250M and 0263.250MXL carry CSA and UR approvals, confirming compliance with applicable safety standards for board mount fuses.

Q: What is the melting I²t specification, and why is it important for substitution?

A: The melting I²t value of 0.0165 defines the thermal energy required to melt the fuse element. This parameter must match exactly between substitute parts to ensure identical protection characteristics and circuit behavior.

Q: Can these fuses be used in both AC and DC applications?

A: Yes. Both parts are rated for 250 V AC/DC operation, as specified in their detailed descriptions. The 250 V rating applies to both alternating and direct current applications.