{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"SFH640-2","brand":"Vishay","brandSlug":"vishay","productSlug":"SFH640-2","canonicalUrl":"https://icboms.com/vishay/SFH640-2","factsUrl":"https://icboms.com/api/mcp/products/SFH640-2","rawCanonicalId":null},"summary":{"shortDescription":"Vishay SFH640-2 optocoupler, 1-channel DC input, transistor with base output, 5300Vrms isolation, 63-125% CTR at 10mA, 300V output rating, 6-DIP through-hole package, -55 to 100°C.","salesMarkdown":"## 5300Vrms isolation — where this optocoupler fits The Vishay SFH640-2 is a single-channel phototransistor optocoupler with a base connection, packaged in a 6-DIP through-hole housing (0.300\" pin spacing). Its 5300Vrms isolation rating puts it in the class used for reinforced insulation in motor drives, industrial PSU feedback loops, and PLC digital input modules — anywhere you need to pass a DC-level signal across a safety barrier without galvanic coupling. The current transfer ratio is specified at 63% minimum to 125% maximum, both measured at 10 mA forward current. That 2:1 spread is tight enough that you can pick a single load resistor value and still guarantee the output saturates across temperature and device-to-device variation — no need to bin or overdrive the LED. The transistor-with-base output (pin 6) lets you pull the base low to force the output off faster, or add a speed-up capacitor between base and collector to shave the 5.5 µs fall time. ## 300V output — not just a logic-level switch Rated Vce(max) of 300V means the output transistor can switch 48V or 120V DC rails directly, not just 5V or 24V logic. The 50 mA per-channel current limit is modest — enough to drive a small relay coil or a gate resistor on a downstream MOSFET, but not a contactor. If you need more current, the base-drive access lets you add an external transistor stage without a second optocoupler. ## Temperature range and package reality Rated from -55°C to 100°C operating, so it lives in outdoor telecom cabinets, engine-bay electronics, and unheated factory floors without derating. The 6-DIP through-hole package is a standard 7.62 mm pitch — no special footprint, easy to hand-assemble or wave-solder. The base connection is the sixth pin; if you are replacing a 4-pin optocoupler, the extra pin needs a pad or a no-connect. ## Lifecycle and sourcing posture It is ROHS3 compliant.","metaTitle":"SFH640-2 Optocoupler, 5300Vrms, 63-125% CTR, 6-DIP","metaDescription":"SFH640-2 optocoupler: 5300Vrms isolation, 63-125% CTR at 10mA, 300V output, -55 to 100°C. Request quote.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Optoisolators"],"specifications":{"Package":"Tube","Input Type":"DC","Output Type":"Transistor with Base","Mounting Type":"Through Hole","Package / Case":"6-DIP (0.300\\\", 7.62mm)","lifecycle_stage":"eol_hot","Number of Channels":"1","Voltage - Isolation":"5300Vrms","Vce Saturation (Max)":"400mV","Operating Temperature":"-55°C ~ 100°C","Rise / Fall Time (Typ)":"2.5µs, 5.5µs","Voltage - Output (Max)":"300V","Supplier Device Package":"6-DIP","Current - Output / Channel":"50mA","Current Transfer Ratio (Max)":"125% @ 10mA","Current Transfer Ratio (Min)":"63% @ 10mA","Voltage - Forward (Vf) (Typ)":"1.1V","Turn On / Turn Off Time (Typ)":"5µs, 6µs","Current - DC Forward (If) (Max)":"60 mA"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$1.82","stockQuantity":0,"priceTiers":[{"qty":1,"price":"$1.82000","currency":"USD"},{"qty":10,"price":"$1.21000","currency":"USD"},{"qty":100,"price":"$0.93140","currency":"USD"},{"qty":500,"price":"$0.84194","currency":"USD"},{"qty":1000,"price":"$0.72354","currency":"USD"},{"qty":2000,"price":"$0.68408","currency":"USD"},{"qty":5000,"price":"$0.66829","currency":"USD"},{"qty":10000,"price":"$0.65776","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/1a937422baabf2206d39857802103d2b.pdf","sourceUrl":null},"ai":{"faq":[{"question":"Does SFH640-2 have a base connection?","answer":"Yes. The output is a phototransistor with a separate base pin (pin 6 in the 6-DIP package). This allows external base drive or speed-up components."},{"question":"What is the current transfer ratio (CTR) of SFH640-2?","answer":"The CTR is specified at 63% minimum and 125% maximum, both at 10 mA forward current. This 2:1 range is typical for a standard-grade phototransistor coupler."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/vishay/SFH640-2","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/vishay/SFH640-2 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-17T19:50:00.618Z","lastPublished":"2026-07-17T19:50:00.618Z","indexable":true}}