{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"1N6635US","brand":"Microchip Technology","brandSlug":"microchip","productSlug":"1N6635US","canonicalUrl":"https://icboms.com/microchip/1N6635US","factsUrl":"https://icboms.com/api/mcp/products/1N6635US","rawCanonicalId":null},"summary":{"shortDescription":"Microchip Technology 1N6635US Zener Diode, 4.3 V nominal, 5 W, ±5% tolerance, SQ-MELF E case, D-5B package, surface mount, -65°C to 175°C.","salesMarkdown":"## Active production — parametric fit for the BOM The 1N6635US: This is a current-production Zener diode you can spec into a new design without worrying about a last-time-buy window closing before the product ships. Nominal Zener voltage is 4.3 V at 5 W total power dissipation with ±5% tolerance. That tolerance band — 4.085 V to 4.515 V — is tight enough for a rail clamp or a voltage-reference leg in a 5 V supply, but not a precision bandgap substitute. The 500 Ohm maximum Zener impedance (Zzt) means the regulation slope is moderate; expect the voltage to shift with current density through the junction. ## SQ-MELF E case — hermetic surface-mount footprint The SQ-MELF E (D-5B) package is a hermetic, non-cavity, metallurgically sealed surface-mount case. It mates with the standard MELF footprint — no lead frame, no plastic overmold. The hermetic seal and the -65°C to 175°C operating range are the two specs that separate this part from a commercial SOT-23 Zener; this is the junction temperature band for avionics, downhole instrumentation, and satellite power buses. Reverse leakage is 25 µA at 1 V reverse voltage, and forward voltage is 1.5 V max at 1 A forward current. These matter in a clamp circuit: the leakage current at the knee determines how much the protected rail droops before the Zener starts conducting.","metaTitle":"Microchip 1N6635US Zener Diode, 4.3 V, 5 W, SQ-MELF","metaDescription":"Active-production 4.3 V Zener diode, 5 W, ±5% tolerance, SQ-MELF E case. -65°C to 175°C range. Sourced and quoted to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Discrete Semiconductors"],"specifications":{"Mfr":"Microchip Technology","Series":"-","Package":"Bulk","Tolerance":"±5%","Power - Max":"5 W","Mounting Type":"Surface Mount","Package / Case":"SQ-MELF, E","Product Status":"Active","lifecycle_stage":"eol_hot","Base Product Number":"1N6635","Impedance (Max) (Zzt)":"500 Ohms","Operating Temperature":"-65°C ~ 175°C","Supplier Device Package":"D-5B","Voltage - Zener (Nom) (Vz)":"4.3 V","Current - Reverse Leakage @ Vr":"25 µA @ 1 V","Voltage - Forward (Vf) (Max) @ If":"1.5 V @ 1 A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$12.6201","priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/d8f5875a647571c98402a6a536757bfe.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/1N6635US/alternatives.json"},"ai":{"faq":[{"question":"What is the tolerance and power rating of 1N6635US?","answer":"The Zener voltage is 4.3 V nominal with ±5% tolerance, and the maximum power dissipation is 5 W. The ±5% band is standard for a Zener regulator or clamp; for a precision reference you would step up to a ±1% or ±2% grade in the same family."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/microchip/1N6635US","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/microchip/1N6635US 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}}