{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"LM317LZ/LFT4","brand":"Texas Instruments","brandSlug":"texas-instruments","productSlug":"LM317LZ-LFT4","canonicalUrl":"https://icboms.com/texas-instruments/LM317LZ-LFT4","factsUrl":"https://icboms.com/api/mcp/products/LM317LZ%2FLFT4","rawCanonicalId":null},"summary":{"shortDescription":"Texas Instruments LM317LZ/LFT4, adjustable positive voltage regulator, 100mA output, 1.2V to 37V output range, 40V input max, PSRR 80dB~65dB at 120Hz, -40°C to 125°C, TO-92-3 through-hole package.","salesMarkdown":"## Adjustable regulation in a TO-92-3 — what the 100mA ceiling means The LM317LZ/LFT4 is a 100mA adjustable positive voltage regulator in a TO-92-3 through-hole package — the current ceiling is the first fit check: this is a low-dropout bias supply for op-amp rails, MCU Vref, or sensor front-ends, not a main power rail pass element. Output adjusts from 1.2V up to 37V with two external resistors, and the 40V input maximum gives headroom for unregulated supplies up to 36V nominal. ## PSRR and protection — the design-in details PSRR runs 80dB to 65dB at 120Hz — that 80dB floor at line frequency is relevant when the input comes from a full-wave rectified supply; the rejection drops at higher frequencies, so post-regulation filtering may be needed for switching-noise-sensitive loads. Built-in over-current, over-temperature, and short-circuit protection mean the regulator handles a momentary output short without cascading failure — a practical advantage in breadboard or field-repair scenarios where the load might fault before the supply is sequenced. Quiescent current is 5 mA — not a micropower LDO, but acceptable for always-on bias rails where the load current is in the tens of milliamps and the Iq is a small fraction of the total budget. ## Temperature grade and board-level fit The TO-92-3 package is a three-lead through-hole form factor — it protrudes above the board and is hand-solderable, making it a common choice for rework, prototyping, and low-volume production where SMD reflow is not justified. Available in Cut Tape and Tape & Box packaging — the Tape & Box option suits automated insertion for through-hole assembly lines, while Cut Tape works for smaller quantities or hand-loading.","metaTitle":"LM317LZ/LFT4 Adjustable Regulator, 100mA, TO-92-3, Active","metaDescription":"LM317LZ/LFT4 adjustable positive voltage regulator, 100mA output, 40V input max, PSRR 80dB~65dB at 120Hz, -40°C to 125°C, TO-92-3.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Power Management (PMIC / Gate Driver)"],"specifications":{"Mfr":"Texas Instruments","PSRR":"80dB ~ 65dB (120Hz)","Series":"-","Package":"Cut Tape (CT); Tape & Box (TB)","Output Type":"Adjustable","Mounting Type":"Through Hole","Package / Case":"TO-226-3, TO-92-3 (TO-226AA)","Product Status":"Active","lifecycle_stage":"eol_hot","Control Features":"-","Current - Output":"100mA","Base Product Number":"LM317","Protection Features":"Over Current, Over Temperature, Short Circuit","Number of Regulators":"1","Output Configuration":"Positive","Operating Temperature":"-40°C~125°C","Voltage - Input (Max)":"40V","Voltage Dropout (Max)":"-","Voltage - Output (Max)":"37V","Supplier Device Package":"TO-92-3","Current - Quiescent (Iq)":"5 mA","Voltage - Output (Min/Fixed)":"1.2V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$0.8900","priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/6e1b4db1f31e3d4f44355e3bccdda90e.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/LM317LZ%2FLFT4/alternatives.json"},"ai":{"faq":[{"question":"What is the PSRR of LM317LZ/LFT4?","answer":"The PSRR is 80dB to 65dB at 120Hz. The 80dB figure is the rejection at the low end of that range — typical for a linear regulator rejecting 120Hz ripple from a full-wave rectified line. The rejection rolls off above line frequency, so switching-noise attenuation is lower without additional post-filtering."},{"question":"Is LM317LZ/LFT4 obsolete?","answer":"The LM317 family has been in continuous production across multiple manufacturers for decades, so supply risk is low for new and existing designs."},{"question":"What package does LM317LZ/LFT4 come in?","answer":"It ships in a TO-92-3 (TO-226AA) through-hole package, available in Cut Tape or Tape & Box formats. The three-lead TO-92 body is the standard low-power transistor-style package — hand-solderable and compatible with socket strips for prototyping."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/texas-instruments/LM317LZ-LFT4","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/texas-instruments/LM317LZ-LFT4 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-22T18:03:28.771Z","lastPublished":"2026-07-22T18:03:28.771Z","indexable":true}}