{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"SN74ALS21AD","brand":"Texas Instruments","brandSlug":"texas-instruments","productSlug":"SN74ALS21AD","canonicalUrl":"https://icboms.com/texas-instruments/SN74ALS21AD","factsUrl":"https://icboms.com/api/mcp/products/SN74ALS21AD","rawCanonicalId":null},"summary":{"shortDescription":"Texas Instruments 74ALS series, AND Gate, 2-circuit, 4-input, Surface Mount, 14-SOIC, 4.5V ~ 5.5V supply, 0°C ~ 70°C, 15ns @ 5V, 50pF max propagation delay.","salesMarkdown":"## Dual 4-input AND gate in 14-SOIC — 74ALS logic for 5 V bus glue The Texas Instruments SN74ALS21AD is a dual 4-input AND gate from the 74ALS family, packaged in a 14-SOIC (0.154\", 3.90 mm width) for surface-mount assembly. It operates from a 4.5 V to 5.5 V supply and is specified over the commercial temperature range of 0°C to 70°C. Typical applications include address decoding, clock gating, and general-purpose combinatorial logic in 5 V TTL systems where propagation delay and output drive matter. ## 15 ns propagation delay — timing margin in 5 V buses The 15 ns max propagation delay at 5 V and 50 pF load sets the timing budget for address decode or control signal paths. At 5 V nominal, this gate keeps combinatorial delays under 15 ns. ## Active production — no end-of-life concern The SN74ALS21AD carries an Active product status and is ROHS3 compliant. There is no last-time-buy or obsolescence notice on record. For dual-sourcing or supply resilience, the 74ALS family includes functionally similar gates such as the SN74ALS38BNSR (quad 2-input NAND, open-collector output) — but that part differs in logic function and output type, so verify the logic equation before substituting. The SN74HC21N is a 74HC-series dual 4-input AND gate in a through-hole package, but its 2 V to 6 V supply range and wider temperature grade (-40°C to 85°C) make it a different fit for a pure 5 V TTL design.","metaTitle":"SN74ALS21AD TI AND Gate, 2-ch 4-input, 15 ns, 14-SOIC","metaDescription":"TI SN74ALS21AD dual 4-input AND gate in 14-SOIC. 15 ns propagation delay at 5 V, 4.5–5.5 V supply, 0–70 °C. Active production, ROHS3. Order to RFQ.","metaKeywords":null},"attributes":{"series":"74ALS","packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Discrete Semiconductors"],"specifications":{"Series":"74ALS","Package":"Tube","Logic Type":"AND Gate","Mounting Type":"Surface Mount","Package / Case":"14-SOIC (0.154\\\", 3.90mm Width)","lifecycle_stage":"eol_hot","Number of Inputs":"4","Voltage - Supply":"4.5V ~ 5.5V","Number of Circuits":"2","Operating Temperature":"0°C ~ 70°C","Input Logic Level - Low":"0.8V","Supplier Device Package":"14-SOIC","Input Logic Level - High":"2V","Current - Output High, Low":"400µA, 8mA","Max Propagation Delay @ V, Max CL":"15ns @ 5V, 50pF"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$1.26","stockQuantity":0,"priceTiers":[{"qty":1,"price":"$1.26000","currency":"USD"},{"qty":10,"price":"$1.12300","currency":"USD"},{"qty":25,"price":"$1.06560","currency":"USD"},{"qty":100,"price":"$0.87520","currency":"USD"},{"qty":250,"price":"$0.81816","currency":"USD"},{"qty":500,"price":"$0.72302","currency":"USD"},{"qty":1000,"price":"$0.57081","currency":"USD"},{"qty":2500,"price":"$0.53850","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/68c3a913ae1f12fb0b56a46bbe4eae01.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What is the difference between SN74ALS21AD and SN74ALS21AN?","answer":"The suffix 'D' indicates the 14-SOIC surface-mount package, while 'N' typically denotes a through-hole DIP package. The logic function and electrical specifications are identical; the choice depends on your board assembly process."},{"question":"Can I use SN74ALS21AD in place of 74LS21?","answer":"Yes, the SN74ALS21AD is a drop-in functional replacement for a 74LS21 dual 4-input AND gate in most 5 V TTL systems. The ALS family offers lower power consumption and similar speed. Verify the input threshold levels (0.8 V low, 2 V high) match your system's noise margins."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/texas-instruments/SN74ALS21AD","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/texas-instruments/SN74ALS21AD 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}}