{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"74FCT521ATSOG","brand":"Renesas Electronics","brandSlug":"renesas","productSlug":"74FCT521ATSOG","canonicalUrl":"https://icboms.com/renesas/74FCT521ATSOG","factsUrl":"https://icboms.com/api/mcp/products/74FCT521ATSOG","rawCanonicalId":null},"summary":{"shortDescription":"Renesas 74FCT521ATSOG, 8-bit identity comparator, active-low output, 7.2 ns propagation delay at 5V, 50 pF, industrial temperature -40°C to 85°C, 20-SOIC package.","salesMarkdown":"## 8-bit identity comparator in 20-SOIC The Renesas 74FCT521ATSOG is an 8-bit identity comparator from the 74FCT series. It compares two 8-bit words and asserts the output when they match. The output is active-low, so a low signal on the A=B pin indicates equality. This part is used in address decoding, data bus matching, and parity-check circuits where a fast, glitch-free match signal is needed. The 20-SOIC package (7.50 mm width) is a common footprint for board-level glue logic. Output drive capability is 15 mA sinking and 48 mA sourcing, enough to feed a standard TTL input or drive an LED indicator through a series resistor. ## Supply and timing — what matters for the bus Quiescent current is only 10 µA, so the part adds negligible draw to the 5V rail when idle. The active current will be higher when inputs toggle, but for a glue-logic comparator this is rarely a power-budget concern. ## Lifecycle and compliance The 74FCT521ATSOG is listed as Active in production. It is ROHS3 compliant, so it passes the material restrictions for EU and most global markets without an exemption claim.","metaTitle":"74FCT521ATSOG 8-Bit Identity Comparator, 20-SOIC, Active","metaDescription":"74FCT521ATSOG 8-bit identity comparator, active-low output, 7.2 ns propagation delay at 5V. Industrial temp -40°C to 85°C. ROHS3 compliant.","metaKeywords":null},"attributes":{"series":"74FCT","packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["DC-DC Power Modules"],"specifications":{"Type":"Identity Comparator","Output":"Active Low","Series":"74FCT","Package":"Tube","Mounting Type":"Surface Mount","Number of Bits":"8","Package / Case":"20-SOIC (0.295\\\", 7.50mm Width)","Output Function":"A=B","lifecycle_stage":"eol_hot","Voltage - Supply":"4.75V ~ 5.25V","Operating Temperature":"-40°C ~ 85°C","Supplier Device Package":"20-SOIC","Current - Quiescent (Iq)":"10 µA","Current - Output High, Low":"15mA, 48mA","Max Propagation Delay @ V, Max CL":"7.2ns @ 5V, 50pF"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$2.92","stockQuantity":0,"priceTiers":[{"qty":1,"price":"$2.92000","currency":"USD"},{"qty":10,"price":"$2.62000","currency":"USD"},{"qty":25,"price":"$2.47720","currency":"USD"},{"qty":100,"price":"$2.14680","currency":"USD"},{"qty":250,"price":"$2.03668","currency":"USD"},{"qty":500,"price":"$1.82750","currency":"USD"},{"qty":1000,"price":"$1.54126","currency":"USD"},{"qty":2500,"price":"$1.46420","currency":"USD"},{"qty":5000,"price":"$1.40915","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/a6b33f1329736edc904c1e93760715a2.pdf","sourceUrl":null},"ai":{"faq":[{"question":"Is 74FCT521ATSOG RoHS compliant?","answer":"Yes, it is ROHS3 compliant."},{"question":"What is the closest pin-compatible alternative to 74FCT521ATSOG?","answer":"Within the 74FCT series, other 8-bit identity comparators in 20-SOIC with active-low output share the same footprint and function. The key difference is propagation delay and supply range — verify the timing and voltage tolerance against your specific BOM before substituting."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/renesas/74FCT521ATSOG","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/renesas/74FCT521ATSOG 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}}