{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"6N139W","brand":"onsemi","brandSlug":"onsemi","productSlug":"6N139W","canonicalUrl":"https://icboms.com/onsemi/6N139W","factsUrl":"https://icboms.com/api/mcp/products/6N139W","rawCanonicalId":null},"summary":{"shortDescription":"onsemi 6N139W Optoisolator, 1-channel DC input, Darlington with Base output, 500% min CTR at 1.6mA, 2500Vrms isolation, 8-DIP through hole, -40°C to 85°C.","salesMarkdown":"## 500% minimum CTR — low-input-current drive for legacy logic interfaces The 6N139W guarantees a current transfer ratio of at least 500% at a forward current of just 1.6 mA. That means a standard TTL or CMOS gate output can drive the input LED directly without a buffer transistor — the 1.3V typical forward drop and 1.6 mA drive are well within the sink capability of a 74LS or 4000-series gate. The Darlington output stage with a separate base terminal gives you the option to add an external base-emitter resistor. Pulling the base down with a few hundred kΩ speeds up the turn-off time by sweeping stored charge out of the Darlington pair — useful when the 7 µs typical turn-off is marginal for your baud rate. onsemi lists the 6N139W as Obsolete. The 8-DIP (0.400-inch, 10.16 mm body width) through-hole package mates with legacy PCB layouts that expect the standard 300-mil row spacing. If you are migrating a design, the Darlington-with-Base pinout is shared with several industry-standard optoisolators — confirm the base pin connection before substituting any alternative. ## 2500Vrms isolation — safety barrier for industrial signal paths The 2500Vrms isolation rating qualifies the 6N139W for basic insulation in mains-connected equipment per IEC 60950-1 reinforced insulation requirements when two devices are used in series. In practice, this part is a fit for breaking ground loops between a PLC output module and a 24 VDC solenoid driver, or for isolating a microcontroller UART from a high-side gate driver referenced to a different ground plane. Maximum continuous output current is 60 mA per channel at 18 V collector-emitter — enough to drive a small relay coil or an opto-MOSFET gate directly, but not a 24 V industrial load without an external transistor.","metaTitle":"onsemi 6N139W Optoisolator, Darlington Output, 500% CTR","metaDescription":"onsemi 6N139W optoisolator, 1-channel DC input, Darlington with Base output, 500% min CTR at 1.6mA, 2500Vrms isolation, -40°C to 85°C.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Obsolete","categoryPath":["Optoisolators"],"specifications":{"Mfr":"onsemi","Series":"-","Package":"Tube","Input Type":"DC","Output Type":"Darlington with Base","Mounting Type":"Through Hole","Package / Case":"8-DIP (0.400\\\", 10.16mm)","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-MDIP","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":"$1.0800","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/b62d34c60f4ce21d8bd4b22e173d60f9.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What is the 6N139W's input type and output configuration?","answer":"The input is DC-coupled (LED anode/cathode). The output is a Darlington pair with the base brought out to a separate pin, allowing external speed-up or base-drive resistors. This is not a logic-gate output — it is an open-collector Darlington rated 60 mA and 18 V maximum."},{"question":"What package does the 6N139W come in?","answer":"The 6N139W is supplied in a through-hole 8-DIP package with a 0.400-inch (10.16 mm) body width. The supplier device package designation is 8-MDIP. It ships in tubes."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/onsemi/6N139W","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/onsemi/6N139W when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-21T06:24:53.064Z","lastPublished":"2026-07-21T06:24:53.064Z","indexable":true}}