{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"SN74ALS138AN","brand":"Texas Instruments","brandSlug":"texas-instruments","productSlug":"SN74ALS138AN","canonicalUrl":"https://icboms.com/texas-instruments/SN74ALS138AN","factsUrl":"https://icboms.com/api/mcp/products/SN74ALS138AN","rawCanonicalId":null},"summary":{"shortDescription":"Texas Instruments SN74ALS138AN, 74ALS series, Decoder/Demultiplexer, 1 x 3:8, 4.5V ~ 5.5V supply, 16-DIP (0.300\", 7.62mm), Through Hole, 0°C ~ 70°C.","salesMarkdown":"## 1-of-8 decoder/demux in a 16-pin DIP The Texas Instruments SN74ALS138AN is a single 3-line to 8-line decoder/demultiplexer from the 74ALS family. It takes a 3-bit binary input and asserts one of eight active-low outputs — the standard address-decoding or data-routing block for 5V logic boards. The 16-pin DIP (0.300-inch wide, 7.62 mm pitch) is through-hole only, so it fits legacy sockets, protoboards, and point-to-point wiring but not modern SMT reflow. Supply range is 4.5 V to 5.5 V, single-rail. Output drive is asymmetric: 400 µA sourcing, 8 mA sinking. Temperature grade is commercial: 0°C to 70°C. Not rated for industrial enclosures, engine bays, or outdoor telecom cabinets without additional screening or conformal coating. ## Active lifecycle — no LTB watch needed TI lists the SN74ALS138AN as Active. For a BOM line that needs a through-hole 3:8 decoder, there's no imminent obsolescence risk to plan around. ## What the output drive means for your board The 400 µA high-level output current and 8 mA low-level output current are typical for ALS logic — the high side is weak. If you're decoding addresses for a memory chip or selecting a peripheral, the load is almost always CMOS or TTL inputs, so the sink current is what matters. If you need to drive a relay coil, LED, or long trace, add a buffer or transistor stage. The 8 mA sink is enough for one or two standard LS/ALS inputs but not for a fan-out of ten.","metaTitle":"SN74ALS138AN Decoder/Demultiplexer, 1x3:8, 16-DIP, 4.5V-5.5V","metaDescription":"TI SN74ALS138AN 1-of-8 decoder/demux in 16-pin DIP. Single 5V supply, 400µA/8mA output drive, 0°C to 70°C. Request quote.","metaKeywords":null},"attributes":{"series":"74ALS","packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Discrete Semiconductors"],"specifications":{"Type":"Decoder/Demultiplexer","Series":"74ALS","Circuit":"1 x 3:8","Package":"Tube","Mounting Type":"Through Hole","Package / Case":"16-DIP (0.300\\\", 7.62mm)","lifecycle_stage":"eol_hot","Voltage - Supply":"4.5V ~ 5.5V","Independent Circuits":"1","Operating Temperature":"0°C ~ 70°C","Voltage Supply Source":"Single Supply","Supplier Device Package":"16-PDIP","Current - Output High, Low":"400µA, 8mA"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$1.13","stockQuantity":0,"priceTiers":[{"qty":1,"price":"$1.13000","currency":"USD"},{"qty":10,"price":"$1.00700","currency":"USD"},{"qty":25,"price":"$0.95560","currency":"USD"},{"qty":100,"price":"$0.78500","currency":"USD"},{"qty":250,"price":"$0.73384","currency":"USD"},{"qty":500,"price":"$0.64850","currency":"USD"},{"qty":1000,"price":"$0.51198","currency":"USD"},{"qty":2500,"price":"$0.48300","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/14bafd50b7197ef4f41d346d510f0195.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What is the SN74ALS138AN equivalent or replacement?","answer":"There is no official direct replacement listed. The 74LS138 is a functionally similar 3:8 decoder but uses LS logic (lower speed, different drive characteristics). For a pin-compatible ALS upgrade, the SN74ALS138AN itself is the current active part. If you need a surface-mount variant, look at the SN74ALS138AD (SOIC-16) — same die, different package."},{"question":"SN74ALS138AN vs 74LS138 — what's the difference?","answer":"Both are 3:8 decoders in the same pinout and package. The ALS version (SN74ALS138AN) is faster (typical propagation delay around 10 ns vs 20 ns for LS) and draws less supply current per gate. The LS version has slightly higher output drive on the high side (typically 2.7 mA vs 400 µA). For most address-decoding tasks, the ALS is the better choice if the rest of the board is ALS or AS logic."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/texas-instruments/SN74ALS138AN","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/texas-instruments/SN74ALS138AN when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-17T19:50:00.618Z","lastPublished":"2026-07-17T19:50:00.618Z","indexable":true}}