{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"045101.5MRL","brand":"Littelfuse Inc.","brandSlug":"littelfuse-inc","productSlug":"045101.5MRL","canonicalUrl":"https://icboms.com/littelfuse-inc/045101.5MRL","factsUrl":"https://icboms.com/api/mcp/products/045101.5MRL","rawCanonicalId":null},"summary":{"shortDescription":"Littelfuse Inc. NANO²® 451 series, Board Mount SMD Fuse, 045101.5MRL, 1.5 A, 125 V AC/DC, Fast Blow, 50 A Breaking Capacity, 2-SMD Square End Block.","salesMarkdown":"## 1.5 A fast-blow SMD fuse for board-level overcurrent protection The Littelfuse 045101.5MRL is a 1.5 A, 125 V AC/DC fast-blow SMD fuse from the NANO²® 451 series, housed in a 2-SMD square end block package measuring 6.10 mm x 2.69 mm x 2.69 mm. It protects sensitive circuits on the board where a cartridge-style fuse won't fit — think power inputs on industrial controls, telecom line cards, or battery-management modules that need a compact, surface-mount overcurrent interrupt. ## Breaking capacity and inrush handling Rated breaking capacity is 50 A at 125 V AC or DC — enough to clear a hard short on a low-impedance bus without the fuse body rupturing. The 0.853 melting I²t tells you how much energy the fuse absorbs before opening: a downstream capacitor bank or motor start that dumps more than 0.853 A²s will blow it on the first surge, so budget the inrush profile against this number. Cold resistance is 0.063 ohms, which at 1.5 A continuous drops about 95 mV and dissipates roughly 140 mW — negligible for most boards, but worth checking if the fuse sits in a tightly regulated 1.8 V rail where every millivolt counts. The fast-blow characteristic means it opens quickly on overcurrent but may nuisance-blow on repetitive inrush pulses that exceed the I²t rating.","metaTitle":"Littelfuse 045101.5MRL NANO² 451 SMD Fuse, 1.5 A, 125 V","metaDescription":"Littelfuse 045101.5MRL NANO² 451 SMD fuse, 1.5 A, 125 V AC/DC, fast-blow, 50 A breaking capacity. Active production. Quoted 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) Cut Tape (CT)","Fuse Type":"Board Mount (Cartridge Style Excluded)","Melting I²t":"0.853","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":"0.063 Ohms","Voltage Rating - AC":"125 V","Voltage Rating - DC":"125 V","Current Rating (Amps)":"1.5 A","Operating Temperature":"-55°C ~ 125°C","Breaking Capacity @ Rated Voltage":"50A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$1.4600","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/2e33e7b2503f3f5110226be89402b64a.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What compliance documentation does Littelfuse provide for the 045101.5MRL?","answer":"The fuse is approved by CSA, PSE, and UL. Littelfuse typically provides RoHS and REACH compliance declarations on request; contact us with your RFQ for the specific documentation set."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/littelfuse-inc/045101.5MRL","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/littelfuse-inc/045101.5MRL 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}}