{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"4N29SM","brand":"onsemi","brandSlug":"onsemi","productSlug":"4N29SM","canonicalUrl":"https://icboms.com/onsemi/4N29SM","factsUrl":"https://icboms.com/api/mcp/products/4N29SM","rawCanonicalId":null},"summary":{"shortDescription":"onsemi 4N29SM, single-channel DC-input optoisolator, Darlington with base output, 4170Vrms isolation, 100% CTR min at 10mA, -40°C to 100°C, 6-SMD Gull Wing package.","salesMarkdown":"## Isolation barrier and output drive The 4N29SM provides 4170Vrms galvanic isolation between a DC input LED and a Darlington with base output transistor, rated for continuous output current up to 150mA per channel. Minimum current transfer ratio of 100% at 10mA forward current ensures the output can saturate with modest LED drive, suiting logic-level interfacing in PLCs and motor drives. The Darlington configuration with base access allows external pull-up or speed-up networks, useful when switching inductive loads or driving a second transistor stage. ## Switching speed and saturation voltage Turn-on time is 5µs typical, while turn-off extends to 40µs maximum — the Darlington's high gain trades off switching speed, so this part is better suited to 10-50 kHz PWM or DC-level shifting than fast serial links. Vce saturation is capped at 1V, keeping the output voltage drop low enough to drive 5V logic families without an extra pull-up resistor. ## Temperature grade and application environment Rated for -40°C to 100°C operating ambient, the 4N29SM fits industrial control cabinets, outdoor telecom enclosures, and engine-bay electronics where commercial-grade parts would drift or fail. The 30V maximum output voltage and 80mA maximum LED forward current set the rail and drive limits — derate the output current above 25°C per the onsemi datasheet curve.","metaTitle":"4N29SM onsemi Optoisolator – 4170Vrms, Darlington Output","metaDescription":"onsemi 4N29SM optoisolator: 4170Vrms isolation, Darlington with base output, 100% CTR min, -40°C to 100°C, 6-SMD Gull Wing. Active production, ROHS3.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Optoisolators"],"specifications":{"Package":"Tube","Input Type":"DC","Output Type":"Darlington with Base","Mounting Type":"Surface Mount","Package / Case":"6-SMD, Gull Wing","lifecycle_stage":"eol_hot","Number of Channels":"1","Voltage - Isolation":"4170Vrms","Vce Saturation (Max)":"1V","Operating Temperature":"-40°C ~ 100°C","Voltage - Output (Max)":"30V","Supplier Device Package":"6-SMD","Current - Output / Channel":"150mA","Current Transfer Ratio (Min)":"100% @ 10mA","Voltage - Forward (Vf) (Typ)":"1.2V","Turn On / Turn Off Time (Typ)":"5µs, 40µs (Max)","Current - DC Forward (If) (Max)":"80 mA"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$1.06","stockQuantity":0,"priceTiers":[{"qty":1,"price":"$1.06000","currency":"USD"},{"qty":10,"price":"$0.66900","currency":"USD"},{"qty":100,"price":"$0.49500","currency":"USD"},{"qty":500,"price":"$0.45484","currency":"USD"},{"qty":1000,"price":"$0.37457","currency":"USD"},{"qty":2000,"price":"$0.35584","currency":"USD"},{"qty":5000,"price":"$0.34781","currency":"USD"},{"qty":10000,"price":"$0.33979","currency":"USD"},{"qty":25000,"price":"$0.33444","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/3b7a0e595c13b969737948a1da9a0357.pdf","sourceUrl":null},"ai":{"faq":[{"question":"Is there a pin-compatible alternative to the 4N29SM?","answer":"The 4N29SM uses the standard 6-SMD Gull Wing footprint common to many Darlington-output optocouplers. Parts like the 4N32 or 4N33 from onsemi share the same pinout but differ in CTR and switching speed — confirm the CTR minimum and Vce sat before substituting."},{"question":"Is the 4N29SM RoHS compliant?","answer":"Yes, onsemi lists it as ROHS3 compliant, meaning it is free of the six restricted substances plus four phthalates under EU RoHS."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/onsemi/4N29SM","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/onsemi/4N29SM when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-17T20:07:01.400Z","lastPublished":"2026-07-17T20:07:01.400Z","indexable":true}}