{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"FOD4218","brand":"onsemi","brandSlug":"onsemi","productSlug":"FOD4218","canonicalUrl":"https://icboms.com/onsemi/FOD4218","factsUrl":"https://icboms.com/api/mcp/products/FOD4218","rawCanonicalId":null},"summary":{"shortDescription":"onsemi FOD4218 optoisolator, triac output, 1 channel, 5000 Vrms isolation, 800 V off-state, 6-DIP through-hole package, tube.","salesMarkdown":"## Isolation and off-state voltage — the safety barrier The FOD4218: Rated for 5000 Vrms isolation between input and output — this is the reinforced-insulation level required for mains-isolated control interfaces in industrial equipment. The 800 V off-state voltage gives headroom above 480 VAC line peaks (which sit around 678 V peak), so the triac blocks the full mains swing without avalanche. The 10 kV/µs minimum static dV/dt means the output triac does not false-trigger on fast voltage transients from inductive load switching or relay contact bounce — a key spec for snubberless or minimal-snubber designs. ## Drive current and firing — low-power interface The 1.28 V typical forward voltage at 30 mA max forward current means the LED drop is predictable across the operating temperature range of -55°C to 100°C. No zero-crossing circuit — the triac fires on the first gate pulse regardless of the AC line phase. This suits phase-angle firing applications (heater control, dimming) where the turn-on point is modulated, not just on/off switching at zero-cross. ## Package and board integration — 6-DIP through-hole Through-hole mounting suits prototype builds, high-vibration environments where socketed or soldered DIPs are preferred over SMT, and rework-friendly designs. Supplied in tube packaging — the tube quantity is the standard handling unit for through-hole DIP devices at assembly houses. ## Approvals and compliance — regulatory acceptance Carries cUL, FIMKO, and UL approvals — accepted in North American (UL/cUL) and European (FIMKO as a CB-scheme member) installations. ROHS3 compliant per onsemi's current material declaration.","metaTitle":"onsemi FOD4218 Optoisolator, Triac Output, 5000 Vrms, 6-DIP","metaDescription":"onsemi FOD4218 optoisolator with triac output, 5000 Vrms isolation, 800 V off-state, 10 kV/µs dV/dt. Active production, ROHS3 compliant. Sourced to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Optoisolators"],"specifications":{"Package":"Tube","Output Type":"Triac","Turn On Time":"60µs","Mounting Type":"Through Hole","Package / Case":"6-DIP (0.300\\\", 7.62mm)","Approval Agency":"cUL, FIMKO, UL","lifecycle_stage":"eol_hot","Number of Channels":"1","Static dV/dt (Min)":"10kV/µs","Current - Hold (Ih)":"500µA","Voltage - Isolation":"5000Vrms","Voltage - Off State":"800 V","Operating Temperature":"-55°C ~ 100°C","Zero Crossing Circuit":"No","Supplier Device Package":"6-DIP","Voltage - Forward (Vf) (Typ)":"1.28V","Current - DC Forward (If) (Max)":"30 mA","Current - LED Trigger (Ift) (Max)":"1.3mA"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$5.84","stockQuantity":30,"priceTiers":[{"qty":1,"price":"$5.84000","currency":"USD"},{"qty":10,"price":"$4.12700","currency":"USD"},{"qty":100,"price":"$3.38040","currency":"USD"},{"qty":500,"price":"$2.84978","currency":"USD"},{"qty":1000,"price":"$2.61393","currency":"USD"},{"qty":2000,"price":"$2.50584","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/4508d0a74baa9082fd3b0c6c58d4edcd.pdf","sourceUrl":null},"ai":{"faq":[{"question":"Where can I buy FOD4218 and how do I get a price?","answer":"The FOD4218 is sourced to order through independent distribution."},{"question":"Will FOD4218 drop into a board that was specified around MOC3073M without rewiring?","answer":"Both parts are 6-DIP triac-output optoisolators with the same pinout — the FOD4218 fits the same PCB footprint. The key parametric difference is the dV/dt rating: the FOD4218 guarantees 10 kV/µs minimum, while the MOC3073M specifies 1 kV/µs. In a circuit that relied on the MOC3073M's lower dV/dt to avoid false triggering, the FOD4218's higher immunity is not a problem — it is strictly better. No board spin is needed."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/onsemi/FOD4218","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/onsemi/FOD4218 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-22T19:45:10.375Z","lastPublished":"2026-07-22T19:45:10.375Z","indexable":true}}