{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"LM340SX-12/NOPB","brand":"Texas Instruments","brandSlug":"texas-instruments","productSlug":"LM340SX-12-NOPB","canonicalUrl":"https://icboms.com/texas-instruments/LM340SX-12-NOPB","factsUrl":"https://icboms.com/api/mcp/products/LM340SX-12%2FNOPB","rawCanonicalId":null},"summary":{"shortDescription":"Texas Instruments LM340SX-12/NOPB, fixed-output LDO regulator, 12V, 1.5A, 80dB PSRR at 120Hz, DDPAK/TO-263-3, surface mount, active.","salesMarkdown":"## 12V rail regulator — 1.5A output with 80dB ripple rejection The Texas Instruments LM340SX-12/NOPB is a fixed-output positive-voltage linear regulator delivering 12V at up to 1.5A from a maximum 35V input rail. The 80dB PSRR at 120Hz means it attenuates full-wave rectifier ripple by a factor of 10,000 — relevant for powering analog stages or audio circuits where the 100/120Hz fundamental must stay off the supply bus. Maximum dropout is 2V at 1A load, so the input rail needs to stay above 14V to maintain regulation at full current. Below that headroom the output falls out of spec — factor this into the minimum bulk-cap voltage under load. ## Package and thermal — DDPAK/TO-263-3 footprint Surface-mount DDPAK/TO-263-3 (3 leads plus tab). The exposed copper tab on the bottom is the main thermal path — the board layout must connect it to a sufficient copper plane area to keep the junction below the 125°C max operating temperature at 1.5A output. The tab is also the ground return; the datasheet's recommended footprint and via pattern are the starting point for the thermal simulation. Available in Tape & Reel (TR) for automated pick-and-place or Cut Tape (CT) for prototype and low-volume builds. The reel quantity is standard for the DDPAK carrier; the CT option avoids committing to a full reel for engineering samples. ## Protection and compliance — built-in fault tolerance On-chip over-temperature shutdown and short-circuit current limiting protect the regulator and the load from fault conditions. The 8 mA quiescent current is drawn regardless of load — budget this into the system standby power when the 12V rail is enabled but unloaded.","metaTitle":"Texas Instruments LM340SX-12/NOPB, 12V Fixed 1.5A LDO","metaDescription":"Texas Instruments LM340SX-12/NOPB, 12V fixed output LDO regulator, 1.5A, 80dB PSRR at 120Hz, DDPAK/TO-263-3. Active, ROHS3. Quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Power Management (PMIC / Gate Driver)"],"specifications":{"PSRR":"80dB (120Hz)","Package":"Tape & Reel (TR); Cut Tape (CT)","Output Type":"Fixed","Mounting Type":"Surface Mount","Package / Case":"TO-263-4, D²Pak (3 Leads + Tab), TO-263AA","lifecycle_stage":"eol_hot","Current - Output":"1.5A","Protection Features":"Over Temperature, Short Circuit","Number of Regulators":"1","Output Configuration":"Positive","Operating Temperature":"0°C ~ 125°C","Voltage - Input (Max)":"35V","Voltage Dropout (Max)":"2V @ 1A","Supplier Device Package":"DDPAK/TO-263-3","Current - Quiescent (Iq)":"8 mA","Voltage - Output (Min/Fixed)":"12V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$1.97","priceTiers":[{"qty":1,"price":"$1.97000","currency":"USD"},{"qty":10,"price":"$1.76700","currency":"USD"},{"qty":25,"price":"$1.66680","currency":"USD"},{"qty":100,"price":"$1.42020","currency":"USD"},{"qty":250,"price":"$1.33348","currency":"USD"},{"qty":500,"price":"$1.16680","currency":"USD"},{"qty":1000,"price":"$0.96677","currency":"USD"},{"qty":2500,"price":"$0.94350","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/f3872e5e42c11c356e800e32f2654004.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/LM340SX-12%2FNOPB/alternatives.json"},"ai":{"faq":[{"question":"What is the PSRR of LM340SX-12/NOPB and why does it matter?","answer":"The PSRR is 80 dB at 120 Hz. That means ripple on the input at the full-wave rectifier frequency is attenuated by a factor of roughly 10,000 — the output sees about 1 mV of ripple for every 10 V of input ripple. This matters when the 12 V rail feeds sensitive analog or audio circuits that cannot tolerate line-frequency hum."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/texas-instruments/LM340SX-12-NOPB","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/texas-instruments/LM340SX-12-NOPB 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}}