{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"SM30T28AY","brand":"STMicroelectronics","brandSlug":"stmicroelectronics","productSlug":"SM30T28AY","canonicalUrl":"https://icboms.com/stmicroelectronics/SM30T28AY","factsUrl":"https://icboms.com/api/mcp/products/SM30T28AY","rawCanonicalId":null},"summary":{"shortDescription":"STMicroelectronics SM30T28AY, Automotive AEC-Q101 TRANSIL™ Zener, 3000W peak pulse power, 24V standoff, 38.9V clamp, DO-214AB SMC, surface mount.","salesMarkdown":"## Why this 3000W Zener exists for 24V automotive rails The STMicroelectronics SM30T28AY is a single-channel Zener transient voltage suppressor from the TRANSIL™ family, purpose-built for automotive electronics where a 24V nominal rail must survive load-dump and inductive kickback without propagating damage downstream. Its 3000W peak pulse power rating (10/1000µs waveform) handles the energy of a typical alternator field dump, while the 24V reverse standoff voltage sits just above the normal bus voltage so it does not clip during steady-state operation. The 38.9V clamping maximum at 77.1A peak pulse current defines the worst-case voltage the protected circuit sees — a number the downstream DC/DC or ECU input stage must tolerate. ## AEC-Q101 and the 175°C junction — where this part lives AEC-Q101 qualification means the SM30T28AY has passed the automotive stress tests — high-temperature reverse bias, temperature cycling, and humidity — that commercial-grade Zeners skip. For a 24V truck ECU or a battery-management module that sees both arctic cold starts and exhaust-adjacent heat soak, this temperature grade is the difference between a decade of service and a field return at two years. ## Package and mounting — DO-214AB SMC Housed in the SMC package, this is a surface-mount device with a large copper tab for heat sinking into the PCB plane. The SMC footprint is standard across the SM30TY series, so a layout designed for the 24V variant can also populate the 12V or 36V siblings without a board spin.","metaTitle":"STMicroelectronics SM30T28AY Zener, 3000W, AEC-Q101","metaDescription":"STMicroelectronics SM30T28AY is a 3000W peak pulse power Zener in DO-214AB, AEC-Q101 qualified for automotive applications.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Circuit Protection"],"specifications":{"Mfr":"STMicroelectronics","Type":"Zener","Series":"Automotive, AEC-Q101, SM30TY, TRANSIL™","Package":"Tape & Reel (TR); Cut Tape (CT)","Applications":"Automotive","Mounting Type":"Surface Mount","Package / Case":"DO-214AB, SMC","Product Status":"Active","lifecycle_stage":"eol_hot","Power - Peak Pulse":"3000W (3kW)","Base Product Number":"SM30T28","Operating Temperature":"-55°C~175°C(TJ)","Power Line Protection":"No","Capacitance @ Frequency":"-","Supplier Device Package":"SMC","Unidirectional Channels":"1","Voltage - Breakdown (Min)":"26.7V","Voltage - Clamping (Max) @ Ipp":"38.9V","Voltage - Reverse Standoff (Typ)":"24V","Current - Peak Pulse (10/1000µs)":"77.1A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$1.3500","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/c1da1532b421560a6148be51fb30338a.pdf","sourceUrl":null},"ai":{"faq":[{"question":"Is SM30T28AY equivalent to SM30T28A?","answer":"The SM30T28A is the base product number for this family; the 'Y' suffix on SM30T28AY typically denotes the AEC-Q101 automotive qualification. The two share the same electrical ratings — 24V standoff, 3000W peak pulse — but only the 'Y' variant carries the automotive-grade stress testing. For non-automotive designs the SM30T28A may be a cost-effective alternate; for automotive BOMs the SM30T28AY is the correct ordering code."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/stmicroelectronics/SM30T28AY","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/stmicroelectronics/SM30T28AY when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-16T14:45:26.447Z","lastPublished":"2026-07-16T14:45:26.447Z","indexable":true}}