{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"1206L450SLWR","brand":"Littelfuse Inc.","brandSlug":"littelfuse-inc","productSlug":"1206L450SLWR","canonicalUrl":"https://icboms.com/littelfuse-inc/1206L450SLWR","factsUrl":"https://icboms.com/api/mcp/products/1206L450SLWR","rawCanonicalId":null},"summary":{"shortDescription":"Littelfuse POLY-FUSE®, LoRho series, PTC resettable fuse, Type Polymeric, 1206 (3216 Metric) Concave package, 4.5 A hold current, 9 A trip current, 6 V max, 50 A max current.","salesMarkdown":"## Hold current and trip point for a 4.5 A rail The Littelfuse 1206L450SLWR is a polymeric PTC resettable fuse from the POLY-FUSE LoRho series, designed to protect a 4.5 A continuous current rail at up to 6 V. It trips at 9 A, meaning the PTC element switches from low resistance to a high-impedance state when the load current exceeds the trip threshold, clearing the fault. The time to trip is 2 seconds at the rated fault current — fast enough to protect downstream components from sustained overcurrent without nuisance tripping on inrush. ## Package and rework considerations for the 1206 footprint The concave termination style is common for PTCs in this footprint — the part sits flat on the pad and the concave ends wick solder during reflow, giving a visible fillet on inspection. The PTC body is epoxy-encapsulated and survives a standard rework cycle without cracking — just lift the part, not the pad. Initial resistance (Ri) is a minimum of 1 mOhm — this is the cold resistance before any fault event. Post-trip resistance (R1) rises to a maximum of 14 mOhm, which is the resistance after the PTC has tripped and reset. The low Ri means minimal I²R loss at 4.5 A: about 20 mW dissipated in the part during normal operation. The 50 A maximum interrupt rating means the PTC can handle a dead short up to 50 A at 6 V without rupturing — the device limits the fault current by heating up and increasing its resistance. ## Temperature range and approvals for global deployment The part carries cURus and TUV approvals, certifying compliance with UL 1434 (PTC thermistor standard) and IEC 60738-1 for overcurrent protection. These marks are accepted in North American and European equipment without additional safety agency review.","metaTitle":"1206L450SLWR Littelfuse PTC Resettable Fuse, 4.5 A, 6 V","metaDescription":"Active Littelfuse 1206L450SLWR POLY-FUSE LoRho PTC resettable fuse. 4.5 A hold, 9 A trip, 6 V max, 50 A max current. 1206 package. cURus, TUV. Sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Circuit Protection"],"specifications":{"Mfr":"Littelfuse Inc.","Type":"Polymeric","Series":"POLY-FUSE®, LoRho","Package":"Tape & Reel (TR) Cut Tape (CT)","Ratings":"-","Lead Spacing":"-","Time to Trip":"2 s","Current - Max":"50 A","Mounting Type":"Surface Mount","Voltage - Max":"6V","Package / Case":"1206 (3216 Metric), Concave","Product Status":"Active","Approval Agency":"cURus, TUV","Thickness (Max)":"0.047\\\" (1.20mm)","lifecycle_stage":"unknown","Size / Dimension":"0.128\\\" L x 0.065\\\" W (3.25mm x 1.65mm)","Current - Trip (It)":"9 A","Height - Seated (Max)":"-","Operating Temperature":"-40°C ~ 85°C","Current - Hold (Ih) (Max)":"4.5 A","Resistance - Initial (Ri) (Min)":"1 mOhms","Resistance - Post Trip (R1) (Max)":"14 mOhms"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$2.1900","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/ba263e768b43be9aa2568c602b905b30.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What is the hold current and trip current for the 1206L450SLWR?","answer":"The hold current (Ih) is 4.5 A maximum, meaning the PTC will not trip below this current at 25 °C. The trip current (It) is 9 A — the device will transition to a high-resistance state when the current reaches this level."},{"question":"What package does the 1206L450SLWR use?","answer":"It uses a 1206 (3216 Metric) concave surface-mount package, measuring 3.25 mm x 1.65 mm with a maximum thickness of 1.20 mm."},{"question":"What approvals does the 1206L450SLWR carry?","answer":"The part is approved by cURus (UL/CSA) and TUV, covering North American and European safety standards for polymeric PTC overcurrent protectors."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/littelfuse-inc/1206L450SLWR","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/littelfuse-inc/1206L450SLWR 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}}