RUSBF090-AP Equivalent & Substitute Parts

Part Overview

The RUSBF090-AP is a polymeric PTC resettable fuse manufactured by Littelfuse Inc., designed for circuit protection in applications requiring 16V, 900 mA hold current specifications. This component features a through-hole radial disc package and is part of the PolySwitch® series. The RUSBF090-AP is currently listed as obsolete, making identification of functionally equivalent alternatives essential for ongoing design support and component procurement.

Substiute Parts

RUSBF090-AP

Littelfuse Inc.In Stock: 1098RUSBF090-AP Datasheet

Current PartRFQ

RUSBF090-2

LittelfuseIn Stock: 7989RUSBF090-2 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the RUSBF090-AP is determined by strict equivalence across electrical and mechanical parameters. The primary substitute, RUSBF090-2, maintains identical specifications across all critical protection characteristics: maximum voltage rating (16V), hold current (900 mA), trip current (1.8 A), time to trip (1.2 s), and resistance parameters (Ri min 70 mOhms, R1 max 180 mOhms). Both components share the same through-hole radial disc package configuration, physical dimensions, and lead spacing, ensuring direct mechanical compatibility. The key differentiator is product status: RUSBF090-AP is obsolete, while RUSBF090-2 is active, and packaging format (RUSBF090-2 is supplied in cut tape).

Parameter Comparison

Engineering Selection Recommendations

The RUSBF090-2 is the direct functional equivalent for RUSBF090-AP replacement. Both components are manufactured by Littelfuse and carry identical electrical protection characteristics and mechanical specifications. The RUSBF090-2 holds active product status, ensuring continued availability and manufacturing support. Both parts maintain equivalent regulatory compliance with CSA, TUV, and UL approvals, and both meet ROHS3 requirements. The RUSBF090-2 is supplied in cut tape packaging, which is standard for active production components. Selection of RUSBF090-2 eliminates obsolescence risk while maintaining full electrical and mechanical compatibility with existing circuit designs.

Frequently Asked Questions (FAQ)

Q: Can RUSBF090-2 be used as a direct replacement for RUSBF090-AP? A: Yes. Both components are electrically and mechanically identical across all specified parameters, including voltage rating, current ratings, resistance characteristics, and physical dimensions. The RUSBF090-2 is the active production equivalent.

Q: What is the difference between RUSBF090-AP and RUSBF090-2? A: The primary difference is product status and packaging format. RUSBF090-AP is obsolete, while RUSBF090-2 is active. RUSBF090-2 is supplied in cut tape packaging, standard for current production. All electrical and mechanical specifications are identical.

Q: Are the physical dimensions identical between these parts? A: Yes. Both components share identical through-hole radial disc package dimensions of 0.291" L x 0.122" W (7.40mm x 3.10mm), with identical lead spacing of 0.199" (5.05mm). PCB layout compatibility is maintained.

Q: Do both parts meet the same regulatory standards? A: Yes. Both RUSBF090-AP and RUSBF090-2 carry identical approvals from CSA, TUV, and UL, and both are ROHS3 compliant.

Q: Why is RUSBF090-AP listed as obsolete? A: Littelfuse has transitioned the RUSBF090 series to active production under the RUSBF090-2 designation. The obsolete status reflects the manufacturer's product lifecycle management.