{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"LD1117AS18TR","brand":"STMicroelectronics","brandSlug":"stmicroelectronics","productSlug":"LD1117AS18TR","canonicalUrl":"https://icboms.com/stmicroelectronics/LD1117AS18TR","factsUrl":"https://icboms.com/api/mcp/products/LD1117AS18TR","rawCanonicalId":null},"summary":{"shortDescription":"STMicroelectronics LD1117AS18TR, fixed 1.8 V output, 1 A low-dropout linear regulator in SOT-223 (TO-261-4) surface-mount package, 80 dB PSRR at 120 Hz, active lifecycle, ROHS3 compliant.","salesMarkdown":"## 1.8 V fixed LDO for clean analog rails The LD1117AS18TR is a fixed 1.8 V output, 1 A low-dropout linear regulator from STMicroelectronics, housed in a SOT-223 (TO-261-4) surface-mount package. Output is positive and fixed at 1.8 V, with a maximum input of 15 V. The 1.3 V dropout at 1 A means the input rail needs to stay above 3.1 V to maintain regulation at full load — a 3.3 V rail works, but margin is tight under transient dips. ## Dropout, quiescent current, and protection Dropout voltage is specified at 1.3 V maximum at 1 A output — that is the headroom the input must hold above 1.8 V. On-chip protection includes over-current and over-temperature shutdown. No reverse-current protection or foldback — if the output is forced above the input, the internal pass transistor conducts backwards. A Schottky diode from output to input is cheap insurance if the load can back-drive the rail. ## Active lifecycle, SOT-223 hand-soldering The SOT-223 package has a large centre tab that acts as the thermal pad and the output connection. Hand-soldering is straightforward with a fine-tip iron and flux — the tab wets quickly. The tape-and-reel (TR) or cut-tape (CT) packaging options let you order production reels or a few pieces for prototyping.","metaTitle":"LD1117AS18TR – STMicro 1.8V Fixed 1A LDO, SOT-223, Active","metaDescription":"STMicroelectronics LD1117AS18TR: 1.8V fixed output, 1A LDO in SOT-223. 80dB PSRR at 120Hz, dropout 1.3V max at 1A. Active lifecycle, ROHS3. Sourced per RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Analog & Data Acquisition"],"specifications":{"Mfr":"STMicroelectronics","PSRR":"80dB (120Hz)","Series":"-","Package":"Tape & Reel (TR); Cut Tape (CT)","Output Type":"Fixed","Mounting Type":"Surface Mount","Package / Case":"TO-261-4, TO-261AA","Product Status":"Active","lifecycle_stage":"eol_hot","Control Features":"-","Current - Output":"1A","Base Product Number":"LD1117","Protection Features":"Over Current, Over Temperature","Number of Regulators":"1","Output Configuration":"Positive","Operating Temperature":"0°C~125°C","Voltage - Input (Max)":"15V","Voltage Dropout (Max)":"1.3V @ 1A","Voltage - Output (Max)":"-","Supplier Device Package":"SOT-223","Current - Quiescent (Iq)":"10 mA","Voltage - Output (Min/Fixed)":"1.8V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$0.9000","priceTiers":[{"qty":1,"price":"$0.90000","currency":"USD"},{"qty":10,"price":"$0.80700","currency":"USD"},{"qty":25,"price":"$0.76600","currency":"USD"},{"qty":100,"price":"$0.62920","currency":"USD"},{"qty":250,"price":"$0.58820","currency":"USD"},{"qty":500,"price":"$0.51982","currency":"USD"},{"qty":1000,"price":"$0.45168","currency":"USD"},{"qty":2500,"price":"$0.45168","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/1f53874c71a4fc18a5ab2ae913a72296.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/LD1117AS18TR/alternatives.json"},"ai":{"faq":[{"question":"Does the LD1117AS18TR require external capacitors?","answer":"Like most LDOs, the LD1117AS18TR needs input and output capacitors for stability — typically 10 µF tantalum or aluminium electrolytic on the output, with a 0.1 µF ceramic in parallel for high-frequency decoupling. The datasheet application circuit shows the recommended values and ESR range. Without them the regulator may oscillate under load transients."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/stmicroelectronics/LD1117AS18TR","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/stmicroelectronics/LD1117AS18TR 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}}