{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"1N6643US","brand":"Microchip Technology","brandSlug":"microchip","productSlug":"1N6643US","canonicalUrl":"https://icboms.com/microchip/1N6643US","factsUrl":"https://icboms.com/api/mcp/products/1N6643US","rawCanonicalId":null},"summary":{"shortDescription":"Microchip Technology 1N6643US fast recovery diode, Standard type, 50 V reverse, 300 mA average, 20 ns trr, SQ-MELF D-5B package, Bulk.","salesMarkdown":"The 1N6643US comes in a surface-mount SQ-MELF, B case, supplier device package D-5B. This hermetic ceramic package is built for high-reliability environments — the MELF barrel sits flat on the board and the metalized end caps take the solder joint, so the diode handles thermal cycling without cracking the body. The D-5B footprint is compact enough for dense layouts but the end-cap pads need a full-width land pattern to carry the 300 mA average current without lifting the termination. ## Switching speed and recovery behaviour This is a fast recovery diode — the JEDEC classification is Fast Recovery =< 500ns, > 200mA (Io), but the actual reverse recovery time (trr) is 20 ns. That 20 ns number is what matters for a 50 V, 300 mA rectifier: it means the diode sweeps out stored charge fast enough to keep switching losses low in a 100–200 kHz converter, and it avoids the snap-off ringing you get with an ultrafast part in a low-current snubber. The 5 pF junction capacitance at 0 V, 1 MHz adds negligible AC loading in signal or clamp applications. ## Thermal and electrical limits Junction temperature range is -65°C to 175°C — that is the full military temperature band. The 1.2 V forward drop at 100 mA is typical for a fast-recovery die in this voltage class; at the 300 mA rated average current the Vf will climb a bit, but the 175°C Tj max gives headroom for conduction losses in a 70°C ambient. Reverse leakage is 50 nA at 50 V, 25°C — it doubles roughly every 10°C, so at 125°C expect around 3 µA, still well within the leakage budget for most precision analog or hold-up capacitor circuits.","metaTitle":"Microchip 1N6643US Fast Recovery Diode, 50V 300mA D-5B","metaDescription":"1N6643US fast recovery diode, 50V 300mA, 20ns trr, SQ-MELF D-5B. Active production from Microchip. Sourced to order; availability confirmed at RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"RoHS non-compliant","productStatus":"Active","categoryPath":["Discrete Semiconductors"],"specifications":{"Mfr":"Microchip Technology","Speed":"Fast Recovery =< 500ns, > 200mA (Io)","Series":"-","Package":"Bulk","Diode Type":"Standard","Mounting Type":"Surface Mount","Package / Case":"SQ-MELF, B","Product Status":"Active","lifecycle_stage":"eol_hot","Base Product Number":"1N6643","Capacitance @ Vr, F":"5pF @ 0V, 1MHz","Supplier Device Package":"D-5B","Reverse Recovery Time (trr)":"20 ns","Current - Reverse Leakage @ Vr":"50 nA @ 50 V","Voltage - DC Reverse (Vr) (Max)":"50 V","Current - Average Rectified (Io)":"300mA","Operating Temperature - Junction":"-65°C~175°C","Voltage - Forward (Vf) (Max) @ If":"1.2 V @ 100 mA"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$7.0800","priceTiers":[{"qty":1,"price":"$7.08000","currency":"USD"}]},"links":{"datasheetUrl":null,"sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/1N6643US/alternatives.json"},"ai":{"faq":[{"question":"What is the reverse recovery time (trr) of the 1N6643US?","answer":"The 1N6643US has a reverse recovery time of 20 ns. This places it solidly in the fast-recovery class (JEDEC Fast Recovery =< 500ns, > 200mA Io) but with actual switching speed an order of magnitude faster than the class floor — suitable for 100–200 kHz rectification or snubber duty."},{"question":"What package does the 1N6643US use?","answer":"It uses a surface-mount SQ-MELF, B case, also designated D-5B. This is a hermetic ceramic barrel package with metalized end caps — standard for military/aerospace grade diodes where glass-passivated or plastic packages are not permitted."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/microchip/1N6643US","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/microchip/1N6643US 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}}