{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"SMAJ154A-TR","brand":"STMicroelectronics","brandSlug":"stmicroelectronics","productSlug":"SMAJ154A-TR","canonicalUrl":"https://icboms.com/stmicroelectronics/SMAJ154A-TR","factsUrl":"https://icboms.com/api/mcp/products/SMAJ154A-TR","rawCanonicalId":null},"summary":{"shortDescription":"STMicroelectronics SMAJ, TRANSIL™, Type Zener, 154V reverse standoff, 317V clamp, 400W peak pulse power, 7A (8/20µs), 1 unidirectional channel, DO-214AC SMA, -55°C~150°C.","salesMarkdown":"## What this TRANSIL™ does on your board The STMicroelectronics SMAJ154A-TR is a unidirectional transient voltage suppressor from the SMAJ TRANSIL™ family, built as a Zener-type clamping device. The 154 V reverse standoff voltage means the part will not conduct appreciably below that rail voltage, so it sits across a 150 V or similar DC bus without leakage issues. ## Clamping voltage and the downstream survival budget The 317 V maximum clamping voltage at Ipp is the number your downstream MOSFET, controller, or capacitor must survive without avalanche breakdown or dielectric rupture. If your DC bus is 150 V nominal, the clamp allows a 167 V headroom above the rail before the TVS starts conducting hard — that is a reasonable margin for a 200 V-rated downstream device. The 171 V minimum breakdown voltage gives a guard band: the part begins to avalanche before the clamp voltage is reached, so a 150 V bus sees no leakage until a transient pushes past 171 V. That 21 V window between standoff and breakdown is typical for this voltage class and means the part does not wear out from repetitive low-energy spikes below the breakdown threshold.","metaTitle":"STMicroelectronics SMAJ154A-TR TVS Diode, 400W, DO-214AC","metaDescription":"STMicroelectronics SMAJ154A-TR TRANSIL™ TVS diode, 154V standoff, 317V clamp, 400W peak pulse power, DO-214AC SMA package, -55°C to 150°C. Active lifecycle.","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":"SMAJ154","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)":"171V","Voltage - Clamping (Max) @ Ipp":"317V","Voltage - Reverse Standoff (Typ)":"154V","Current - Peak Pulse (10/1000µs)":"7A (8/20µs)"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$0.5400","priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/cb45a0c551131e855efff64db719fd1e.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/SMAJ154A-TR/alternatives.json"},"ai":{"faq":[{"question":"What is the closest pin-compatible alternative to SMAJ154A-TR in this component family?","answer":"Within the same SMAJ TRANSIL™ series, the SMAJ154A-TR is the unidirectional 154 V variant. The bidirectional counterpart (SMAJ154CA-TR) shares the same DO-214AC footprint and voltage ratings but uses two back-to-back Zener junctions for AC signal line protection. If your application is DC and unidirectional, stick with the A suffix; if you need bidirectional clamping, the CA suffix is the pin-compatible swap."},{"question":"Is SMAJ154A-TR RoHS compliant?","answer":"The SMAJ154A-TR is part of ST's standard TRANSIL offering and is manufactured to be RoHS compliant. The TR suffix indicates Tape & Reel packaging, which is the standard lead-free, RoHS-compliant shipping format for this series."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/stmicroelectronics/SMAJ154A-TR","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/stmicroelectronics/SMAJ154A-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}}