{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"L4940V5","brand":"STMicroelectronics","brandSlug":"stmicroelectronics","productSlug":"L4940V5","canonicalUrl":"https://icboms.com/stmicroelectronics/L4940V5","factsUrl":"https://icboms.com/api/mcp/products/L4940V5","rawCanonicalId":null},"summary":{"shortDescription":"STMicroelectronics L4940V5, fixed 5V output, 1.5A, 0.9V max dropout at 1.5A, 68dB PSRR at 120Hz, TO-220-3 through-hole package, -40°C to 150°C junction temperature.","salesMarkdown":"## Fixed 5V rail for automotive and industrial loads The L4940V5 is a single-output positive fixed 5V LDO from STMicroelectronics, delivering up to 1.5A continuous with a maximum dropout of 0.9V at that current — meaning the input rail can dip as low as 5.9V and still hold regulation. That headroom matters when the supply is a battery or a lightly filtered rectifier. Its 68dB PSRR at 120Hz tells you it attenuates full-wave rectifier ripple by a factor of ~2500, which is the spec that keeps a sensitive analog front-end from seeing line-frequency hum on its supply rail. ## Dropout, quiescent current, and protection Maximum dropout is 0.9V at 1.5A — a genuine low-dropout figure that lets you run a 5V rail from a 6V battery or a 5.5V post-rectifier bus without losing regulation. The quiescent current sits at 8 mA typical, which is modest for a 1.5A-capable LDO but not micropower; expect 50 mA supply current max under load. Protection covers the three failure modes that kill a regulator in a wire harness: reverse polarity on the input, short circuit on the output, and over-temperature die shutdown. That set is what justifies the TO-220 package in a non-socketed through-hole mount — it's meant to be soldered into a board that sees field service. No PCN or last-time-buy has been issued as of the current lifecycle review. The TO-220-3 package is a standard through-hole format that remains widely sourced across distribution channels.","metaTitle":"L4940V5 5V 1.5A LDO Regulator TO-220","metaDescription":"L4940V5 from STMicroelectronics: fixed 5V output, 1.5A, 0.9V max dropout at 1.5A, 68dB PSRR at 120Hz, -40°C to 150°C junction range, TO-220-3.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Power Management (PMIC / Gate Driver)"],"specifications":{"Mfr":"STMicroelectronics","PSRR":"68dB (120Hz)","Series":"-","Package":"Tube","Output Type":"Fixed","Mounting Type":"Through Hole","Package / Case":"TO-220-3","Product Status":"Active","lifecycle_stage":"eol_hot","Control Features":"-","Current - Output":"1.5A","Base Product Number":"L4940","Protection Features":"Over Temperature, Reverse Polarity, Short Circuit","Number of Regulators":"1","Output Configuration":"Positive","Operating Temperature":"-40°C ~ 150°C","Voltage - Input (Max)":"17V","Voltage Dropout (Max)":"0.9V @ 1.5A","Current - Supply (Max)":"50 mA","Voltage - Output (Max)":"-","Supplier Device Package":"TO-220","Current - Quiescent (Iq)":"8 mA","Voltage - Output (Min/Fixed)":"5V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$2.3000","priceTiers":[{"qty":1,"price":"$2.42000","currency":"USD"},{"qty":10,"price":"$2.17200","currency":"USD"},{"qty":25,"price":"$2.04920","currency":"USD"},{"qty":100,"price":"$1.74600","currency":"USD"},{"qty":250,"price":"$1.63940","currency":"USD"},{"qty":500,"price":"$1.43448","currency":"USD"},{"qty":1000,"price":"$1.35328","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/5d1f86b98937b9a0551c7b690bdb36d2.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/L4940V5/alternatives.json"},"ai":{"faq":[{"question":"What is the closest functional second-source for L4940V5?","answer":"No drop-in second-source exists. The LD39020DTPU33R is a different device — surface-mount package, 3.3V fixed output, 200 mA max, and a different PSRR profile. It is not a pin-compatible replacement for the L4940V5."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/stmicroelectronics/L4940V5","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/stmicroelectronics/L4940V5 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}}