{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"SMAJ28A-TR","brand":"STMicroelectronics","brandSlug":"stmicroelectronics","productSlug":"SMAJ28A-TR","canonicalUrl":"https://icboms.com/stmicroelectronics/SMAJ28A-TR","factsUrl":"https://icboms.com/api/mcp/products/SMAJ28A-TR","rawCanonicalId":null},"summary":{"shortDescription":"STMicroelectronics SMAJ28A-TR, TRANSIL™ series, Zener TVS diode, 28V reverse standoff, 400W peak pulse power, unidirectional, DO-214AC (SMA) package, surface mount, -55°C to 150°C.","salesMarkdown":"## 28V rail clamp — what the 400W rating buys you Its 400W peak pulse power rating means it can absorb a 39A peak pulse current without failing — useful for protecting a 24V DC bus or a 28V supply line in industrial or telecom gear. ## Breakdown and clamping — the numbers that matter Minimum breakdown voltage is 31.1V, so the part starts conducting before the rail sees damaging overvoltage. Maximum clamping voltage at rated Ipp is 59V — that is the peak voltage the downstream circuitry must survive. The 28V reverse standoff is the continuous DC level the TVS blocks without leakage becoming a problem. ## Package and mounting — DO-214AC SMA Surface-mount DO-214AC (SMA) package, supplied on Tape & Reel or Cut Tape. The small footprint fits tight layouts on a 2-layer board; the cathode band identifies the unidirectional orientation. No power line protection feature — this is a signal/DC rail clamp, not an AC mains suppressor.","metaTitle":"SMAJ28A-TR TVS Diode, 28V Standoff, 400W Peak Pulse","metaDescription":"STMicroelectronics SMAJ28A-TR unidirectional Zener TVS, 28V reverse standoff, 400W peak pulse (10/1000µs), DO-214AC SMA.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Circuit Protection"],"specifications":{"Mfr":"STMicroelectronics","Type":"Zener","Series":"SMAJ, TRANSIL™","Package":"Tape & Reel (TR) Cut Tape (CT)","Applications":"General Purpose","Mounting Type":"Surface Mount","Package / Case":"DO-214AC, SMA","Product Status":"Active","lifecycle_stage":"eol_hot","Power - Peak Pulse":"400W","Base Product Number":"SMAJ28","Operating Temperature":"-55°C ~ 150°C (TJ)","Power Line Protection":"No","Capacitance @ Frequency":"-","Supplier Device Package":"SMA (DO-214AC)","Unidirectional Channels":"1","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":"$0.5100","priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/cb45a0c551131e855efff64db719fd1e.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/SMAJ28A-TR/alternatives.json"},"ai":{"faq":[{"question":"Is SMAJ28A-TR unidirectional or bidirectional?","answer":"Unidirectional — one channel, with the cathode band marked on the DO-214AC package. For bidirectional clamping on an AC signal line you would need the 'A' suffix variant (e.g. SMAJ28CA) from the same series."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/stmicroelectronics/SMAJ28A-TR","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/stmicroelectronics/SMAJ28A-TR 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}}