{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"1206L400SLTH-VYR","brand":"Littelfuse Inc.","brandSlug":"littelfuse-inc","productSlug":"1206L400SLTH-VYR","canonicalUrl":"https://icboms.com/littelfuse-inc/1206L400SLTH-VYR","factsUrl":"https://icboms.com/api/mcp/products/1206L400SLTH-VYR","rawCanonicalId":null},"summary":{"shortDescription":"Littelfuse Inc. POLY-FUSE®, LoRho series PTC resettable fuse, Type Polymeric, 1206 (3216 Metric) Concave package, 4 A hold current, 50 A max, 6 V, AEC-Q200 rated.","salesMarkdown":"## What this PTC resettable fuse does on the board The 1206L400SLTH-VYR is a polymeric PTC resettable fuse from Littelfuse's POLY-FUSE LoRho series, designed for overcurrent protection in low-voltage circuits where low series resistance matters. It holds 4 A continuously (Ih) and trips at 8 A (It), with a maximum interrupt rating of 50 A at 6 V — sized for USB, battery, or low-voltage DC rail protection where the fault current is limited by the supply impedance. The initial resistance is 1 mOhm minimum, rising to 16 mOhm maximum after a trip event — the LoRho construction keeps I²R losses low during normal operation, which matters for power-sensitive designs. ## Obsolete — sourcing through independent channels No pin-compatible drop-in replacement is listed by Littelfuse, so a BOM position using this part requires sourcing existing inventory or qualifying a parametric substitute.","metaTitle":"Littelfuse 1206L400SLTH-VYR PTC Resettable Fuse, 4A Hold","metaDescription":"Littelfuse 1206L400SLTH-VYR POLY-FUSE LoRho PTC resettable fuse, 4A hold current, 50A max, 6V, 1206 package. AEC-Q200. Obsolete; sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Obsolete","categoryPath":["Circuit Protection"],"specifications":{"Mfr":"Littelfuse Inc.","Type":"Polymeric","Series":"POLY-FUSE®, LoRho","Package":"Tape & Reel (TR) Cut Tape (CT)","Ratings":"AEC-Q200","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":"Obsolete","Approval Agency":"cURus, TUV","Thickness (Max)":"0.055\\\" (1.40mm)","lifecycle_stage":"unknown","Size / Dimension":"0.126\\\" L x 0.065\\\" W (3.20mm x 1.65mm)","Current - Trip (It)":"8 A","Height - Seated (Max)":"-","Operating Temperature":"-40°C ~ 85°C","Current - Hold (Ih) (Max)":"4 A","Resistance - Initial (Ri) (Min)":"1 mOhms","Resistance - Post Trip (R1) (Max)":"16 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 trip time for the 1206L400SLTH-VYR?","answer":"The typical time to trip is 2 seconds at the specified overcurrent condition — this is the time for the PTC element to heat up and switch to its high-resistance state after the trip current threshold is exceeded."},{"question":"What approvals does the 1206L400SLTH-VYR carry?","answer":"It is approved by cURus (Canadian/US safety standard for components) and TUV (German product safety certification), confirming it meets recognized safety requirements for polymeric PTC fuses."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/littelfuse-inc/1206L400SLTH-VYR","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/littelfuse-inc/1206L400SLTH-VYR when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-20T14:34:45.345Z","lastPublished":"2026-07-20T14:34:45.345Z","indexable":true}}