{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"STTH108","brand":"STMicroelectronics","brandSlug":"stmicroelectronics","productSlug":"STTH108","canonicalUrl":"https://icboms.com/stmicroelectronics/STTH108","factsUrl":"https://icboms.com/api/mcp/products/STTH108","rawCanonicalId":null},"summary":{"shortDescription":"STMicroelectronics STTH108, Fast Recovery Rectifier, 800 V, 1 A, 75 ns trr, DO-204AL (DO-41) Axial, Through Hole.","salesMarkdown":"## What makes the STTH108 a fast recovery diode — and why it matters That trr figure — well under the 500 ns threshold that defines the 'fast recovery' class — means this diode switches off quickly, reducing turn-off losses in circuits like power-factor-correction (PFC) boost stages, flyback snubbers, and continuous-conduction-mode (CCM) boost converters. The 1.65 V forward voltage drop at 1 A is a trade-off: you get fast switching at the cost of higher conduction loss compared to a standard recovery rectifier. The DO-41 axial package is a through-hole workhorse, easy to hand-solder and retrofit into existing boards. For a buyer managing a BOM line, this means the STTH108 is a candidate for a last-time-buy (LTB) or a planned migration to a pin-compatible successor. The 800 V / 1 A / 75 ns trr combination is common in PFC and flyback circuits, so an alternative with the same DO-41 footprint and similar trr should be sourced before the NRND window closes. ## Reverse recovery time and forward drop — the switching-loss trade-off The 75 ns trr is the headline switching parameter. In a 100 kHz PFC boost stage, a 75 ns trr diode will have significantly lower turn-off losses than a standard 2 µs recovery rectifier, which means less heat to manage and a smaller heatsink. The 1.65 V forward drop at 1 A is on the higher side for a 1 A diode — a standard recovery part might drop 1.0 V at the same current — but that is the price of fast recovery. The 5 µA reverse leakage at 800 V is low enough to not affect efficiency in most offline applications. The junction temperature rating of 175°C maximum gives thermal headroom for cramped layouts or high ambient temperatures.","metaTitle":"STTH108 Fast Recovery Diode, 800 V, 1 A, 75 ns trr, DO-41","metaDescription":"STTH108 fast recovery rectifier: 800 V, 1 A, 75 ns trr in DO-41. RoHS compliant. Quoted on request.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"NRND","categoryPath":["Discrete Semiconductors"],"specifications":{"Mfr":"STMicroelectronics","Speed":"Fast Recovery =< 500ns, > 200mA (Io)","Series":"-","Package":"Cut Tape (CT); Tape & Box (TB)","Diode Type":"Standard","Mounting Type":"Through Hole","Package / Case":"DO-204AL, DO-41, Axial","Product Status":"Not For New Designs","lifecycle_stage":"eol_hot","Base Product Number":"STTH108","Capacitance @ Vr, F":"-","Supplier Device Package":"DO-41","Reverse Recovery Time (trr)":"75 ns","Current - Reverse Leakage @ Vr":"5 µA @ 800 V","Voltage - DC Reverse (Vr) (Max)":"800 V","Current - Average Rectified (Io)":"1A","Operating Temperature - Junction":"175°C(Max)","Voltage - Forward (Vf) (Max) @ If":"1.65 V @ 1 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$0.6600","priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/f18750f10a4c1a5329c268d94c1141c6.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/STTH108/alternatives.json"},"ai":{"faq":[{"question":"What is the replacement for STTH108?","answer":"No official successor is listed by STMicroelectronics. Because the STTH108 is NRND, a pin-compatible fast recovery diode in the same DO-41 package with an 800 V / 1 A rating and a trr of 75 ns or faster is the practical replacement path. The UF4007 is a common 1 A / 1000 V fast recovery diode in DO-41, but its trr is typically 75 ns as well — check the exact trr spec for your switching frequency before substituting."},{"question":"Is STTH108 RoHS compliant?","answer":"Yes, the STTH108 is RoHS compliant. The listing carries no RoHS exemption flag, and the part is lead-free per ST's standard policy for this series."},{"question":"What is the reverse recovery time of STTH108?","answer":"The reverse recovery time (trr) of the STTH108 is 75 ns, measured under standard test conditions. This qualifies it as a fast recovery diode (trr ≤ 500 ns)."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/stmicroelectronics/STTH108","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/stmicroelectronics/STTH108 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-17T19:50:00.618Z","lastPublished":"2026-07-17T19:50:00.618Z","indexable":true}}