{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"SM4T33CAY","brand":"STMicroelectronics","brandSlug":"stmicroelectronics","productSlug":"SM4T33CAY","canonicalUrl":"https://icboms.com/stmicroelectronics/SM4T33CAY","factsUrl":"https://icboms.com/api/mcp/products/SM4T33CAY","rawCanonicalId":null},"summary":{"shortDescription":"STMicroelectronics SM4T33CAY bidirectional Zener TVS diode, Automotive Grade, AEC-Q101 qualified, 28V reverse standoff, 59V clamping, 400W peak pulse power, DO-214AC (SMA) surface-mount package.","salesMarkdown":"Its reverse standoff voltage of 28V means it sits across the supply line without conducting during normal operation, then avalanches at a minimum breakdown of 31.1V to shunt the surge. The maximum clamping voltage of 59V at the peak pulse current tells you the highest voltage the protected circuit will see during a 10/1000µs transient — a 400W peak pulse power rating confirms it can absorb that energy without failing short. This part is AEC-Q101 qualified, so it carries the reliability screening for automotive environments: engine bay, chassis modules, and any 28V bus that sees load-dump or inductive kickback. ## Automotive-grade transient suppression — the AEC-Q101 difference AEC-Q101 qualification means this device passed the Automotive Electronics Council's stress tests for discrete semiconductors: high-temperature reverse bias, temperature cycling, humidity bias, and repeated surge pulses. For a BOM destined for under-hood or chassis-domain electronics, that qualification is the baseline — it saves the qualification paperwork burden and reduces the risk of field failures from marginal parts. ## Package and footprint — DO-214AC (SMA) The SM4T33CAY comes in a DO-214AC (SMA) package, a standard surface-mount footprint for power-handling diodes. The SMA body is small enough for dense PCB layouts but large enough to dissipate the 400W pulse without excessive board copper. Mounting is surface-mount only, so it flows through the same reflow profile as the rest of the board.","metaTitle":"STMicroelectronics SM4T33CAY Bidirectional TVS Diode, 28V","metaDescription":"STMicroelectronics SM4T33CAY bidirectional TVS diode, 28V reverse standoff, 59V clamping, 400W peak pulse, AEC-Q101 qualified, DO-214AC SMA.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Circuit Protection"],"specifications":{"Mfr":"STMicroelectronics","Type":"Zener","Grade":"Automotive","Series":"*","Package":"Tape & Reel (TR) Cut Tape (CT)","Applications":"-","Mounting Type":"Surface Mount","Qualification":"AEC-Q101","Package / Case":"DO-214AC, SMA","Product Status":"Active","lifecycle_stage":"eol_hot","Power - Peak Pulse":"400W","Base Product Number":"SM4T33","Operating Temperature":"-55°C ~ 150°C (TJ)","Power Line Protection":"No","Bidirectional Channels":"1","Capacitance @ Frequency":"-","Supplier Device Package":"SMA (DO-214AC)","Voltage - Breakdown (Min)":"31.1V","Voltage - Clamping (Max) @ Ipp":"59V","Voltage - Reverse Standoff (Typ)":"28V","Current - Peak Pulse (10/1000µs)":"39A (8/20µs)"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$0.9300","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/45721247f0377ca5ff3983c35eddc2fa.pdf","sourceUrl":null},"ai":{"faq":[{"question":"Is SM4T33CAY AEC-Q101 qualified?","answer":"Yes, the SM4T33CAY is AEC-Q101 qualified, making it suitable for automotive applications that require the stress and reliability screening defined by the Automotive Electronics Council."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/stmicroelectronics/SM4T33CAY","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/stmicroelectronics/SM4T33CAY when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:49:49.435Z","lastPublished":"2026-08-11T15:49:49.435Z","indexable":true}}