{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"LM4991LD/NOPB","brand":"Texas Instruments","brandSlug":"texas-instruments","productSlug":"LM4991LD-NOPB","canonicalUrl":"https://icboms.com/texas-instruments/LM4991LD-NOPB","factsUrl":"https://icboms.com/api/mcp/products/LM4991LD%2FNOPB","rawCanonicalId":null},"summary":{"shortDescription":"Texas Instruments Boomer® Class AB audio amplifier, LM4991LD/NOPB, 1-Channel (Mono), 3W output at 3Ohm, 2.2V-5.5V supply, 8-WSON (4x4) surface mount package, industrial temp range.","salesMarkdown":"The LM4991LD/NOPB: That 3W figure is the max output power per channel at 10% THD — in a real portable speaker or alert tone circuit, expect clean output up to about 2W before distortion climbs noticeably. The 8-WSON package with exposed pad (4x4mm footprint) pulls heat through the PCB land pattern. For sustained 3W output into 3Ω, the thermal pad needs a decent copper pour and vias to an inner ground plane — otherwise the die temperature climbs past the 85°C operating limit on a warm day. The shutdown pin lets a GPIO or a power-management IC kill the amplifier current draw when no audio is needed, which matters for battery life in a portable device. ## Depop, shutdown, thermal protection — what each feature actually does Depop (pop-reduction circuitry) suppresses the audible thump when the amplifier turns on or off — without it, the DC offset at the output couples through the speaker and sounds like a relay clicking. The shutdown feature pulls the quiescent current to near zero, so a microcontroller can gate the amplifier between audio bursts without draining the battery. Thermal protection folds back the output drive if the die temperature exceeds the safe limit, preventing destruction from a sustained shorted output or inadequate heatsinking.","metaTitle":"Texas Instruments LM4991LD/NOPB Class AB Audio Amp, 3W","metaDescription":"LM4991LD/NOPB Texas Instruments Boomer® Class AB audio amplifier, 3W mono output, 2.2-5.5V supply, 8-WSON package. Active production, ROHS3 compliant.","metaKeywords":null},"attributes":{"series":"Boomer®","packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Analog & Data Acquisition"],"specifications":{"Type":"Class AB","Series":"Boomer®","Package":"Tape & Reel (TR); Cut Tape (CT)","Features":"Depop, Shutdown, Thermal Protection","Output Type":"1-Channel (Mono)","Mounting Type":"Surface Mount","Package / Case":"8-WDFN Exposed Pad","lifecycle_stage":"eol_hot","Voltage - Supply":"2.2V ~ 5.5V","Operating Temperature":"-40°C ~ 85°C (TA)","Supplier Device Package":"8-WSON (4x4)","Max Output Power x Channels @ Load":"3W x 1 @ 3Ohm"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$1.8","stockQuantity":0,"priceTiers":[{"qty":1,"price":"$1.80000","currency":"USD"},{"qty":10,"price":"$1.61800","currency":"USD"},{"qty":25,"price":"$1.52640","currency":"USD"},{"qty":100,"price":"$1.30050","currency":"USD"},{"qty":250,"price":"$1.22112","currency":"USD"},{"qty":500,"price":"$1.06848","currency":"USD"},{"qty":1000,"price":"$0.88531","currency":"USD"},{"qty":2000,"price":"$0.86400","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/9b516df9fae954dff61416d2384efd07.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What is the maximum output power of the LM4991LD/NOPB?","answer":"For a 4Ω or 8Ω speaker, the output power will be lower — the 3W figure is the max rating at the minimum load impedance."},{"question":"What package does the LM4991LD/NOPB come in?","answer":"It is supplied in an 8-WDFN exposed pad package (also designated 8-WSON, 4x4mm footprint)."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/texas-instruments/LM4991LD-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/LM4991LD-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}}