{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"SM30T30AY","brand":"STMicroelectronics","brandSlug":"stmicroelectronics","productSlug":"SM30T30AY","canonicalUrl":"https://icboms.com/stmicroelectronics/SM30T30AY","factsUrl":"https://icboms.com/api/mcp/products/SM30T30AY","rawCanonicalId":null},"summary":{"shortDescription":"STMicroelectronics SM30T30AY, Automotive AEC-Q101 TRANSIL™ TVS diode, 3000W peak pulse power, 26V reverse standoff, 42.1V clamping, unidirectional, DO-214AB SMC, -55°C to 175°C.","salesMarkdown":"## 3000 W automotive TVS for load-dump and surge protection The STMicroelectronics SM30T30AY is a unidirectional TRANSIL™ TVS diode in the SM30TY series, designed to clamp voltage transients on automotive power rails. It delivers 3000 W peak pulse power per the 10/1000 µs waveform, with a reverse standoff voltage of 26 V and a maximum clamping voltage of 42.1 V at the rated peak pulse current of 71.3 A. ## What the 3 kW rating means for the BOM The 3000 W peak pulse power rating is the part's headline spec — it defines how much transient energy the diode can absorb before failing. For a 12 V automotive system, a 26 V standoff means the diode stays out of conduction during normal battery voltage (up to ~16 V during cold-crank), then clamps hard at 42.1 V to protect downstream regulators and ECUs. The 71.3 A peak pulse current at the clamping voltage gives you the headroom to calculate whether the diode can handle the worst-case surge from a 60 V load-dump event without exceeding its thermal limit. In practice, the 3 kW rating covers most passenger-car load-dump requirements per ISO 7637-2 pulse 5a, but verify the pulse energy against your specific alternator and battery configuration. ## AEC-Q101 and the automotive supply chain The SM30T30AY carries AEC-Q101 qualification, meaning it has passed the automotive-grade stress tests (high-temperature reverse bias, temperature cycling, autoclave, etc.) required for Tier-1 ECU programs. The base product number is SM30T30, indicating a family of voltage-variant parts sharing the same die and package; the 'AY' suffix denotes the specific breakdown and clamping voltage bin. ## Package and mounting: DO-214AB SMC The SM30T30AY is supplied in a DO-214AB (SMC) package, a standard surface-mount footprint for medium-power TVS diodes. The SMC body handles the 3 kW pulse without requiring a heatsink, relying on the PCB copper area for thermal dissipation. The package is compatible with standard pick-and-place equipment and reflow profiles used for automotive PCBA.","metaTitle":"STMicroelectronics SM30T30AY TVS Diode, 3000W, AEC-Q101","metaDescription":"STMicroelectronics SM30T30AY automotive TVS diode, 3000W peak pulse power, 26V standoff, AEC-Q101 qualified, DO-214AB SMC package.","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":"SM30T30","Operating Temperature":"-55°C~175°C(TJ)","Power Line Protection":"No","Capacitance @ Frequency":"-","Supplier Device Package":"SMC","Unidirectional Channels":"1","Voltage - Breakdown (Min)":"28.9V","Voltage - Clamping (Max) @ Ipp":"42.1V","Voltage - Reverse Standoff (Typ)":"26V","Current - Peak Pulse (10/1000µs)":"71.3A"}},"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":"Does SM30T30AY have AEC-Q101 automotive qualification?","answer":"Yes, the SM30T30AY is AEC-Q101 qualified, part of the Automotive SM30TY series. This qualification covers the stress tests required for automotive ECU and under-hood applications."},{"question":"Is SM30T30AY unidirectional or bidirectional?","answer":"The SM30T30AY is a unidirectional TVS diode — it has one anode and one cathode, clamping only positive transients above the breakdown voltage. For bidirectional protection (e.g., on AC lines or signal pairs), a different part from the SM30TY family would be needed."},{"question":"Can SM30T30AY be used as a replacement for SM30T30A?","answer":"The SM30T30AY and SM30T30A share the same base product number SM30T30 and the same DO-214AB package, suggesting a similar die and voltage class. However, verify the exact breakdown voltage and clamping specs from the respective datasheets — the 'Y' and 'A' suffixes may indicate different voltage bins or qualification levels. The SM30T30AY is AEC-Q101 qualified; confirm whether the SM30T30A carries the same automotive grade before substituting in a production BOM."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/stmicroelectronics/SM30T30AY","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/stmicroelectronics/SM30T30AY when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-16T15:42:54.149Z","lastPublished":"2026-07-16T15:42:54.149Z","indexable":true}}