{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"SI8040AA-B-IU","brand":"Skyworks Solutions","brandSlug":"skyworks","productSlug":"SI8040AA-B-IU","canonicalUrl":"https://icboms.com/skyworks/SI8040AA-B-IU","factsUrl":"https://icboms.com/api/mcp/products/SI8040AA-B-IU","rawCanonicalId":null},"summary":{"shortDescription":"Skyworks Solutions SI8040AA-B-IU, General Purpose Digital Isolator, Capacitive Coupling, 4 Channels, Unidirectional, 10Mbps, 1000Vrms, 16-SSOP/QSOP, Tube, -40°C to 125°C.","salesMarkdown":"## Active production — BOM-fit for a 4-channel unidirectional isolator The SI8040AA-B-IU is an active-production general-purpose digital isolator from Skyworks Solutions, built on capacitive coupling technology. It provides four unidirectional isolation channels in a 16-QSOP package, all inputs on side 1 (4/0 configuration), making it a direct fit for applications where the isolated side needs no return data path. The 10 Mbps data rate covers SPI and UART links at moderate bus speeds. ## What the 10 Mbps and 35 kV/µs CMTI mean for your bus The 10 Mbps data rate is the maximum guaranteed toggle rate across the isolation barrier — at this speed the 65 ns max propagation delay and 30 ns pulse-width distortion still leave enough timing margin for a 20 MHz SPI clock (50 ns period) to be recovered cleanly on the secondary side. Below 10 Mbps the timing margin widens further. Common-mode transient immunity of 35 kV/µs means the output does not glitch when a 1 kV/µs step appears across the isolation barrier — a realistic condition in a motor-drive inverter where the IGBT switching node slews at several kV/µs. This CMTI figure is typical for capacitive-coupled isolators in this class and is adequate for most industrial inverter and servo drive applications. The 2.5 ns typical rise/fall time means the output edges are fast enough to drive standard CMOS logic inputs without extra Schmitt-trigger buffering, but the fast edges also couple more noise onto the PCB than a slower isolator — keep the output trace short and avoid routing it near sensitive analog lines. ## Supply rails and temperature grade No isolated DC-DC converter is integrated — the SI8040AA-B-IU provides signal isolation only. The secondary-side circuitry requires its own local supply rail, typically derived from a separate isolated DC-DC module or a bias winding on the system power supply. ## Package and board-fit note Supplied in tube packaging (standard for prototype and low-volume assembly). The 16-QSOP body is 3.90 mm wide — a narrow SOIC derivative with 0.635 mm pin pitch. The footprint is compatible with standard 16-pin SSOP (3.90 mm) land patterns. Surface-mount reflow profile follows standard MSL for this package class; no special moisture-sensitivity bake is required unless the tube seal has been compromised. ## Peer comparison — SI8035AA-B-IU vs SI8040AA-B-IU The closest functional sibling is the SI8035AA-B-IU, which shares the same package, data rate, isolation voltage, propagation delay, CMTI, and temperature grade. The difference is channel count: the SI8035 provides 3 unidirectional channels (3/0 configuration) versus the SI8040's 4 channels (4/0). A board originally laid out for the 3-channel part can accept the 4-channel SI8040 if the fourth input is left unconnected or tied to a logic level — the pinout is the same, only the extra channel is added.","metaTitle":"SI8040AA-B-IU Skyworks Digital Isolator, 4-Ch, 10Mbps","metaDescription":"Active Skyworks SI8040AA-B-IU general-purpose digital isolator. 4 unidirectional channels, 1000Vrms isolation, 10Mbps data rate, -40 to 125°C. 16-QSOP.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Digital Isolators"],"specifications":{"Type":"General Purpose","Package":"Tube","Data Rate":"10Mbps","Technology":"Capacitive Coupling","Channel Type":"Unidirectional","Mounting Type":"Surface Mount","Isolated Power":"No","Package / Case":"16-SSOP (0.154\\\", 3.90mm Width)","lifecycle_stage":"eol_hot","Voltage - Supply":"3.15V ~ 5.5V","Number of Channels":"4","Voltage - Isolation":"1000Vrms","Operating Temperature":"-40°C ~ 125°C","Inputs - Side 1/Side 2":"4/0","Rise / Fall Time (Typ)":"2.5ns, 2.5ns","Supplier Device Package":"16-QSOP","Pulse Width Distortion (Max)":"30ns","Propagation Delay tpLH / tpHL (Max)":"65ns, 65ns","Common Mode Transient Immunity (Min)":"35kV/µs"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$3.75","stockQuantity":16,"priceTiers":[{"qty":1,"price":"$3.75000","currency":"USD"},{"qty":10,"price":"$3.36500","currency":"USD"},{"qty":25,"price":"$3.18160","currency":"USD"},{"qty":100,"price":"$2.75730","currency":"USD"},{"qty":250,"price":"$2.61592","currency":"USD"},{"qty":500,"price":"$2.34724","currency":"USD"},{"qty":1000,"price":"$1.97960","currency":"USD"},{"qty":2500,"price":"$1.88062","currency":"USD"},{"qty":5000,"price":"$1.80992","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/602b3daee45a418a66aed890e4e78a99.pdf","sourceUrl":null},"ai":{"faq":[{"question":"Where can I buy the SI8040AA-B-IU and how do I get a price?","answer":"The SI8040AA-B-IU is an active Skyworks Solutions part, sourced through independent distribution. Submit an RFQ with your target volume and preferred date-code window."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/skyworks/SI8040AA-B-IU","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/skyworks/SI8040AA-B-IU when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-22T19:45:10.375Z","lastPublished":"2026-07-22T19:45:10.375Z","indexable":true}}