{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"TLP291(GB,SE","brand":"Toshiba Semiconductor","brandSlug":"toshiba","productSlug":"TLP291GBSE","canonicalUrl":"https://icboms.com/toshiba/TLP291GBSE","factsUrl":"https://icboms.com/api/mcp/products/TLP291(GB%2CSE","rawCanonicalId":null},"summary":{"shortDescription":"Toshiba TLP291(GB,SE single-channel DC-input transistor-output optocoupler, 3750Vrms isolation, 100-600% CTR at 5mA, 80V output max, 4-SOIC package, Tube, -55°C to 110°C.","salesMarkdown":"The TLP291(GB,SE is a single-channel DC-input, transistor-output optocoupler from Toshiba in a 4-SOIC surface-mount package. Its 3750Vrms isolation rating suits basic or functional isolation in industrial controls, PLC I/O modules, motor-drive feedback, and isolated sensor interfaces where the signal path needs a galvanic barrier without the footprint of a DIP-8. The transistor output with a minimum current transfer ratio of 100% and maximum of 600% at 5 mA forward current gives you headroom to drive logic inputs or small relays directly, while the 80 V output rating handles higher-side switching in 24 V or 48 V industrial rails. Combined with ROHS3 compliance, this part is qualified for ongoing design-in and production without a forced migration timeline. For dual-sourcing flexibility, the TLP291 family includes CTR-binned variants such as TLP291(GR,SE (lower CTR range) and TLP291(BL-TP,SE (higher CTR range), all sharing the same 4-SOIC footprint and 3750Vrms isolation rating. ## Switching speed and CTR — sizing the drive margin That is adequate for isolated digital inputs, relay coil drives, and slow serial buses where the propagation delay is not the timing bottleneck. The 100% minimum CTR at 5 mA forward current means a 5 mA input can deliver at least 5 mA at the output — enough to saturate the transistor and pull a 5 V logic input low with margin. The 300 mV max Vce saturation keeps the on-state voltage drop low, so the output can sink the rated 50 mA per channel without excessive dissipation. ## Temperature range and mounting The 4-SOIC package (4.55 mm body width) is a compact footprint for high-density boards, and the surface-mount format aligns with standard reflow processes. The Tube shipping medium is typical for engineering samples and low-volume production; reeled options (e.g., TLP291(GRL-TP,SE) are available for higher-volume pick-and-place.","metaTitle":"TLP291(GB,SE Optoisolator, 3750Vrms, Transistor Output","metaDescription":"TLP291(GB,SE single-channel optocoupler with 3750Vrms isolation, transistor output, 100-600% CTR at 5mA, -55°C to 110°C. Active, ROHS3 compliant.","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","Mounting Type":"Surface Mount","Package / Case":"4-SOIC (0.179\\\", 4.55mm Width)","lifecycle_stage":"eol_hot","Number of Channels":"1","Voltage - Isolation":"3750Vrms","Vce Saturation (Max)":"300mV","Operating Temperature":"-55°C ~ 110°C","Rise / Fall Time (Typ)":"2µs, 3µs","Voltage - Output (Max)":"80V","Supplier Device Package":"4-SO","Current - Output / Channel":"50mA","Current Transfer Ratio (Max)":"600% @ 5mA","Current Transfer Ratio (Min)":"100% @ 5mA","Voltage - Forward (Vf) (Typ)":"1.25V","Turn On / Turn Off Time (Typ)":"3µs, 3µs","Current - DC Forward (If) (Max)":"50 mA"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$0.59","stockQuantity":0,"priceTiers":[{"qty":1,"price":"$0.59000","currency":"USD"},{"qty":10,"price":"$0.36400","currency":"USD"},{"qty":100,"price":"$0.20910","currency":"USD"},{"qty":1000,"price":"$0.16362","currency":"USD"},{"qty":2000,"price":"$0.14999","currency":"USD"},{"qty":5000,"price":"$0.13635","currency":"USD"},{"qty":10000,"price":"$0.12726","currency":"USD"},{"qty":25000,"price":"$0.12272","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/a8ee6f0a66b20e745d1c9a7a3ea4ce22.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What is the CTR range of TLP291(GB,SE and why does it matter?","answer":"The current transfer ratio is specified at 100% minimum and 600% maximum at 5 mA forward current. A 100% minimum CTR ensures the output transistor can sink at least 5 mA when the LED is driven with 5 mA, which is sufficient to pull a standard TTL/CMOS logic input low. The 600% maximum gives you gain margin for driving loads like small relays or optocoupler cascades without extra buffer stages."},{"question":"What is the replacement or equivalent for TLP291(GB,SE?","answer":"The TLP291 family includes CTR-binned variants that are footprint-compatible and share the same 3750Vrms isolation and 4-SOIC package. TLP291(GR,SE covers a lower CTR range, while TLP291(BL-TP,SE covers a higher CTR range. All are active and ROHS3 compliant. For a direct functional equivalent with the same CTR bin, stick with the (GB) suffix."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/toshiba/TLP291GBSE","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/toshiba/TLP291GBSE 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}}