{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"6N139S","brand":"onsemi","brandSlug":"onsemi","productSlug":"6N139S","canonicalUrl":"https://icboms.com/onsemi/6N139S","factsUrl":"https://icboms.com/api/mcp/products/6N139S","rawCanonicalId":null},"summary":{"shortDescription":"onsemi 6N139S, single-channel DC-input Darlington-with-base optoisolator, 8-SMD Gull Wing package, 2500Vrms isolation, 500% min CTR at 1.6mA If, -40°C to 85°C.","salesMarkdown":"The 6N139S is a single-channel optoisolator from onsemi with a Darlington output transistor and a base pin for external bias or feedback. It accepts DC input and delivers a minimum current transfer ratio of 500% at only 1.6 mA forward current — meaning you can drive the LED side from a low-power logic output or a GPIO pin and still get a solid logic-level signal on the output side. The Darlington-with-base topology gives you a third terminal on the output side (pin 6 on the 8-SMD Gull Wing package) that lets you adjust switching threshold or add a pull-down for noise immunity. Typical turn-on time is 1.5 µs, turn-off is 7 µs — fast enough for PLC input modules, relay drivers, and isolated status feedback, but not for high-speed serial links. ## Obsolete — sourcing and replacement planning The 6N139S is marked obsolete by onsemi. Any remaining inventory is limited to what distributors or brokers hold on the shelf. (2) evaluate a pin-compatible replacement from the same 6N139 family or a similar Darlington-output optoisolator from another manufacturer. The 8-SMD Gull Wing footprint is common, but always verify the CTR, switching speed, and isolation rating against your design margin. The 500% minimum CTR at 1.6 mA If is the headline parameter. It means the output transistor can sink at least 8 mA when the LED is driven at 1.6 mA — enough to pull a 5 V logic input low through a 620 Ω pull-up. If you need more output current, the Darlington can deliver up to 60 mA continuous, but the LED drive must increase proportionally (max 20 mA If). Forward voltage is 1.3 V typical at rated If — a standard LED drop. The output side is rated to 18 V maximum, which covers 5 V and 12 V logic rails but not 24 V industrial supplies without a series resistor or zener clamp. The 8-SMD Gull Wing package is surface-mount — pick-and-place friendly.","metaTitle":"6N139S Optoisolator – onsemi Darlington, 2500Vrms, Obsolete","metaDescription":"6N139S from onsemi: single-channel Darlington output optoisolator, 2500Vrms isolation, 500% min CTR at 1.6mA.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Obsolete","categoryPath":["Discrete Semiconductors"],"specifications":{"Mfr":"onsemi","Series":"-","Package":"Tube","Input Type":"DC","Output Type":"Darlington with Base","Mounting Type":"Surface Mount","Package / Case":"8-SMD, Gull Wing","Product Status":"Obsolete","lifecycle_stage":"eol_hot","Number of Channels":"1","Base Product Number":"6N139","Voltage - Isolation":"2500Vrms","Vce Saturation (Max)":"-","Operating Temperature":"-40°C ~ 85°C","Rise / Fall Time (Typ)":"-","Voltage - Output (Max)":"18V","Supplier Device Package":"8-SMD","Current - Output / Channel":"60mA","Current Transfer Ratio (Max)":"-","Current Transfer Ratio (Min)":"500% @ 1.6mA","Voltage - Forward (Vf) (Typ)":"1.3V","Turn On / Turn Off Time (Typ)":"1.5µs, 7µs","Current - DC Forward (If) (Max)":"20 mA"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$0.7800","priceTiers":[{"qty":1,"price":"$0.81000","currency":"USD"},{"qty":10,"price":"$0.53100","currency":"USD"},{"qty":100,"price":"$0.34770","currency":"USD"},{"qty":1000,"price":"$0.27450","currency":"USD"},{"qty":2000,"price":"$0.25620","currency":"USD"},{"qty":5000,"price":"$0.24705","currency":"USD"},{"qty":10000,"price":"$0.24339","currency":"USD"},{"qty":25000,"price":"$0.23790","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/b62d34c60f4ce21d8bd4b22e173d60f9.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/6N139S/alternatives.json"},"ai":{"faq":[{"question":"How can I order the 6N139S or check availability?","answer":"The 6N139S is obsolete, so standard distributor stock is depleted. We can source it through our supply network — submit an RFQ with your target quantity and we will search open-market inventory and return a quote. Availability and pricing are confirmed at quote time."},{"question":"What is the replacement for the 6N139S?","answer":"onsemi has not published a direct successor for the 6N139S. A pin-compatible alternative within the same family is the 6N139 (through-hole DIP-8) — the S suffix indicates the Gull Wing surface-mount variant. For a surface-mount replacement, look at other Darlington-output optoisolators in 8-SMD Gull Wing from onsemi or competitors such as Toshiba or Vishay, but verify the CTR, isolation, and switching speed against your design. The base pin (pin 6) is not available on all Darlington optos, so check the output configuration."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/onsemi/6N139S","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/onsemi/6N139S 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}}