RUSBF075-1 Polymeric PTC Resettable Fuse Equivalent & Substitute Parts

Part Overview

The RUSBF075-1 is a polymeric PTC resettable fuse manufactured by Littelfuse Inc., designed for overcurrent protection in electronic circuits. This component operates at 6V with a 750 mA hold current and provides automatic reset functionality after fault conditions are cleared. The RUSBF075-1 carries an obsolete product status, making identification of active equivalent parts essential for ongoing design support and procurement continuity.

Substiute Parts

RUSBF075-1

Littelfuse Inc.In Stock: 1145RUSBF075-1 Datasheet

Current PartRFQ

RUSBF075

LittelfuseIn Stock: 3724RUSBF075 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the RUSBF075-1 is determined by strict equivalence across the following electrical and mechanical parameters:

• Voltage rating: 6V maximum
• Current hold specification: 750 mA maximum
• Current trip threshold: 1.3 A
• Maximum current capacity: 40 A
• Time to trip response: 400 ms
• Initial resistance: 110 mOhms minimum
• Post-trip resistance: 230 mOhms maximum
• Operating temperature range: -40°C to 85°C
• Mounting configuration: Through hole radial disc package
• Physical dimensions: 0.272" diameter x 0.122" thickness with 0.201" lead spacing
• Regulatory compliance: CSA, TUV, UL certifications
• Environmental compliance: ROHS3 compliant

The RUSBF075 meets all specified parameters and serves as a direct functional equivalent. The primary distinction between RUSBF075-1 and RUSBF075 is product status and packaging configuration.

Parameter Comparison

Engineering Selection Recommendations

The RUSBF075 is the recommended substitute for the obsolete RUSBF075-1. Both components are manufactured by Littelfuse within the PolySwitch® RUSBF series and maintain identical electrical specifications and physical dimensions. The RUSBF075 holds active product status, ensuring continued availability and manufacturing support. Both parts carry equivalent regulatory certifications (CSA, TUV, UL) and maintain ROHS3 compliance. The RUSBF075 is suitable for direct replacement in applications currently utilizing the RUSBF075-1, with no circuit modifications required.

Frequently Asked Questions (FAQ)

Q: Can RUSBF075 replace RUSBF075-1 in existing designs?

A: Yes. The RUSBF075 provides identical electrical performance and physical compatibility. Both components share the same voltage rating (6V), current hold specification (750 mA), trip current (1.3 A), and operating temperature range (-40°C to 85°C). Physical dimensions and lead spacing are equivalent, allowing direct PCB mounting without layout changes.

Q: What is the difference between RUSBF075-1 and RUSBF075?

A: The primary difference is product status. RUSBF075-1 is obsolete, while RUSBF075 maintains active status. Packaging differs slightly (RUSBF075-1 uses standard packaging; RUSBF075 uses bag packaging). All electrical and mechanical specifications remain identical.

Q: Are both parts certified to the same standards?

A: Yes. Both RUSBF075-1 and RUSBF075 carry CSA, TUV, and UL approvals. Both comply with ROHS3 environmental standards. Regulatory compliance is equivalent across both components.

Q: What parameters determine substitution eligibility?

A: Substitution is based on matching voltage rating (6V), current hold (750 mA), current trip (1.3 A), operating temperature range (-40°C to 85°C), physical dimensions (0.272" diameter x 0.122" thickness), lead spacing (0.201"), and regulatory certifications. All parameters must align for direct replacement.

Q: Is the RUSBF075 available in the same package configuration?

A: Yes. Both components use through-hole radial disc packaging with identical physical dimensions and lead spacing. The RUSBF075 is supplied in bag packaging, which is standard for active production components.