{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"045103.5NRL","brand":"Littelfuse Inc.","brandSlug":"littelfuse-inc","productSlug":"045103.5NRL","canonicalUrl":"https://icboms.com/littelfuse-inc/045103.5NRL","factsUrl":"https://icboms.com/api/mcp/products/045103.5NRL","rawCanonicalId":null},"summary":{"shortDescription":"Littelfuse Inc. NANO²® 451 series, 045103.5NRL surface-mount fast-blow fuse, 3.5 A, 125 V AC/DC, 50 A interrupting rating, 2-SMD square end block package, Tape & Reel.","salesMarkdown":"## Active production, 3.5 A fast-blow fuse for 125 V rails The Littelfuse 045103.5NRL is an active-production surface-mount fuse from the NANO² 451 series, rated 3.5 A at 125 V AC and DC. It clears quickly on high overcurrents (fast-blow response), making it a fit for protecting downstream semiconductors, DC-DC converter input stages, and low-voltage power distribution in industrial control and telecom equipment. ## Breaking capacity and temperature envelope The interrupting rating is 50 A at the rated 125 V — the maximum fault current the fuse can safely clear. For circuits with available fault current above 50 A at 125 V, an upstream current-limiting device or a higher-interrupt fuse is needed. DC cold resistance is 0.02 ohms, which at 3.5 A translates to roughly 0.25 W of self-heating at rated current — negligible for most PCB layouts, but worth noting in high-density designs where adjacent components limit airflow. ## Package and approvals Housed in a 2-SMD, square end block package measuring 6.10 mm x 2.69 mm x 2.69 mm — compatible with standard 2410 (metric 6125) pad layouts. Approvals from CSA, PSE, and UL cover North American and Japanese regulatory acceptance, simplifying BOM compliance for equipment sold into those markets.","metaTitle":"Littelfuse 045103.5NRL NANO² 451 Fuse, 3.5 A, 125 V","metaDescription":"Active Littelfuse 045103.5NRL NANO² 451 surface-mount fuse, 3.5 A, 125 V AC/DC, fast-blow, 50 A breaking capacity, CSA/PSE/UL approved. Sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Circuit Protection"],"specifications":{"Mfr":"Littelfuse Inc.","Color":"-","Series":"NANO²® 451","Package":"Tape & Reel (TR)","Fuse Type":"Board Mount (Cartridge Style Excluded)","Melting I²t":"2.469","Mounting Type":"Surface Mount","Response Time":"Fast Blow","Package / Case":"2-SMD, Square End Block","Product Status":"Active","Approval Agency":"CSA, PSE, UL","lifecycle_stage":"unknown","Size / Dimension":"0.240\\\" L x 0.106\\\" W x 0.106\\\" H (6.10mm x 2.69mm x 2.69mm)","DC Cold Resistance":"0.02 Ohms","Voltage Rating - AC":"125 V","Voltage Rating - DC":"125 V","Current Rating (Amps)":"3.5 A","Operating Temperature":"-55°C ~ 125°C","Breaking Capacity @ Rated Voltage":"50A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$0.5926","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/2e33e7b2503f3f5110226be89402b64a.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What approvals does the 045103.5NRL carry?","answer":"The fuse is approved by CSA, PSE, and UL, covering North American and Japanese safety standards. This simplifies compliance for equipment destined for those regions."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/littelfuse-inc/045103.5NRL","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/littelfuse-inc/045103.5NRL when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:49:49.435Z","lastPublished":"2026-08-11T15:49:49.435Z","indexable":true}}