Littelfuse 0278.800V Equivalent & Substitute Parts

Part Overview

The Littelfuse 0278.800V is a board mount fuse rated for 800 mA at 125 V AC/DC with fast blow response characteristics. This component belongs to the MICRO™ 278 series and is designed for through-hole radial, can, vertical mounting applications. The part is currently active in production with 1038 units in stock. Equivalent substitute parts are identified when identical electrical and mechanical parameters are maintained across the same fuse category, enabling seamless component replacement in circuit designs without performance degradation.

Substiute Parts

0278.800V

Littelfuse Inc.In Stock: 10960278.800V Datasheet

Current PartRFQ

0272.800V

LittelfuseIn Stock: 10100272.800V Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

The Littelfuse 0272.800V qualifies as a parametric equivalent to the 0278.800V based on strict alignment of all critical electrical and mechanical specifications. Substitution eligibility is determined by the following parameters:

Electrical Parameters (Must Match Exactly):

• Current Rating: 800 mA
• Voltage Rating AC: 125 V
• Voltage Rating DC: 125 V
• Response Time: Fast Blow
• Breaking Capacity @ Rated Voltage: 10 kA
• Melting I²t: 0.113
• DC Cold Resistance: 0.271 Ohms

Mechanical Parameters (Must Match Exactly):

• Fuse Type: Board Mount (Cartridge Style Excluded)
• Mounting Type: Through Hole
• Package / Case: Radial, Can, Vertical
• Size / Dimension: 0.235" Dia x 0.287" H (5.97 mm x 7.30 mm)

Compliance Parameters (Must Match Exactly):

• Operating Temperature Range: -55°C ~ 125°C
• Approval Agencies: CSA, QPL, UL
• RoHS Status: ROHS3 Compliant

The 0272.800V differs only in series designation (MICRO™ 272 versus MICRO™ 278), with all functional and physical characteristics remaining identical. This series variation does not affect electrical performance or mechanical compatibility in board mount applications.

Parameter Comparison

Engineering Selection Recommendations

Both the 0278.800V and 0272.800V maintain active product status with full manufacturing support from Littelfuse Inc. Component selection between these parts should be based on availability and supply chain considerations, as electrical performance and mechanical compatibility are functionally equivalent.

The 0278.800V currently maintains higher inventory availability at 1038 units in stock compared to 917 units for the 0272.800V. Both parts carry identical regulatory approvals (CSA, QPL, UL) and RoHS3 compliance certification, ensuring equivalent suitability for applications requiring these certifications.

The series designation difference (MICRO™ 278 versus MICRO™ 272) reflects internal Littelfuse product line organization and does not impact circuit performance, thermal characteristics, or mechanical fit in through-hole board mount applications.

Frequently Asked Questions (FAQ)

Q: Can the 0272.800V be used as a direct replacement for the 0278.800V in existing circuit designs?

A: Yes. The 0272.800V is a parametric equivalent with identical electrical ratings (800 mA, 125 V AC/DC, fast blow response), mechanical dimensions (0.235" Dia x 0.287" H), and mounting characteristics (through-hole radial, can, vertical). No circuit modifications are required.

Q: Are there any differences in breaking capacity or melting characteristics between these parts?

A: No. Both parts specify 10 kA breaking capacity at rated voltage and 0.113 melting I²t, ensuring identical protection performance in overcurrent conditions.

Q: Do both parts meet the same regulatory and compliance standards?

A: Yes. Both the 0278.800V and 0272.800V carry CSA, QPL, and UL approvals, and both are ROHS3 compliant. They are equivalent for applications requiring these certifications.

Q: What is the significance of the series designation difference (MICRO™ 278 versus MICRO™ 272)?

A: The series designation reflects Littelfuse's internal product line categorization. This difference does not affect electrical performance, thermal behavior, or mechanical compatibility in board mount applications.

Q: Are the physical dimensions identical for both parts?

A: Yes. Both parts share identical dimensions of 0.235" Dia x 0.287" H (5.97 mm x 7.30 mm) and use the same radial, can, vertical package configuration, ensuring identical PCB footprint compatibility.

Q: What is the DC cold resistance specification, and is it identical for both parts?

A: Both parts specify 0.271 Ohms DC cold resistance, which determines the resistive voltage drop under normal operating conditions and is identical between the two components.

Q: Can these parts be used in temperature-sensitive applications?

A: Yes. Both parts operate across the identical temperature range of -55°C to 125°C, making them suitable for industrial and extended temperature applications.