{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"LMK00338RTAR","brand":"Texas Instruments","brandSlug":"texas-instruments","productSlug":"LMK00338RTAR","canonicalUrl":"https://icboms.com/texas-instruments/LMK00338RTAR","factsUrl":"https://icboms.com/api/mcp/products/LMK00338RTAR","rawCanonicalId":null},"summary":{"shortDescription":"Texas Instruments LMK00338RTAR, 3:9 differential fanout buffer, no PLL, 400 MHz max, accepts CML/HCSL/HSTL/LVDS/LVPECL/SSTL/crystal, 40-WQFN (6x6), -40 to 85 °C.","salesMarkdown":"## No PLL — pure fanout buffer, not a clock generator The LMK00338RTAR is a 3:9 differential fanout buffer from Texas Instruments. It contains no PLL, so it does not multiply or clean up jitter — it distributes an incoming reference clock to nine outputs with minimal additive phase noise. If your design needs frequency synthesis or spread-spectrum generation, this is the wrong part; if you need to fan out a clean PCIe or SATA reference to multiple endpoints, it is exactly the right one. ## Input flexibility — seven differential standards plus crystal The buffer accepts CML, HCSL, HSTL, LVDS, LVPECL, SSTL, and a single-ended crystal input on the primary clock path. That covers every common high-speed serial interface standard used in PCIe Gen3/Gen4, SATA, and Ethernet reference clock trees. A single BOM line item handles multi-protocol backplanes without level translators. ## 400 MHz ceiling — enough for Gen3, marginal for Gen5 Rated at 400 MHz maximum frequency. That comfortably covers the 100 MHz PCIe reference clock and the 125 MHz SATA reference. For PCIe Gen5 (32 GT/s) the reference is still 100 MHz, so the frequency itself is fine — but the additive jitter at that data rate needs a check against the receiver's total jitter budget. The 3:9 fan-out ratio lets one clock source drive a full root complex and its downstream ports without external repeaters. ## Supply rail and temperature — 3.3 V nominal, industrial range Operates from 3.15 V to 3.45 V — a tight 3.3 V ±4.5 % window. That means it can be designed into new production today without planning a second-source qualification.","metaTitle":"LMK00338RTAR fanout buffer, 400 MHz, 3:9, 40-WQFN","metaDescription":"TI LMK00338RTAR 3:9 differential fanout buffer. No PLL. 400 MHz max. Accepts CML/HCSL/HSTL/LVDS/LVPECL/SSTL/crystal. Active.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Clock & Timing ICs"],"specifications":{"Mfr":"Texas Instruments","PLL":"No","Input":"CML, HCSL, HSTL, LVDS, LVPECL, SSTL, Crystal","Output":"HCSL, LVCMOS","Series":"-","Package":"Tape & Reel (TR); Cut Tape (CT)","Main Purpose":"PCI Express (PCIe), SATA CPU","Mounting Type":"Surface Mount","Package / Case":"40-WFQFN Exposed Pad","Product Status":"Active","Frequency - Max":"400MHz","lifecycle_stage":"eol_hot","Voltage - Supply":"3.15V ~ 3.45V","Number of Circuits":"1","Base Product Number":"LMK00338","Ratio - Input:Output":"3:9","Operating Temperature":"-40°C~85°C","Supplier Device Package":"40-WQFN (6x6)","Differential - Input:Output":"Yes/Yes"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$3.9700","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/f9848e2dda8581c37e0c2117def14c57.pdf","sourceUrl":null},"ai":{"faq":[{"question":"Is LMK00338RTAR a PLL or a fanout buffer?","answer":"It is a fanout buffer with no PLL. It does not generate or multiply clocks — it distributes an incoming reference to nine outputs."},{"question":"What output types does LMK00338RTAR support?","answer":"It outputs HCSL and LVCMOS levels."},{"question":"What is the difference between LMK00338 and LMK00334?","answer":"The LMK00338 provides a 3:9 input-to-output ratio; the LMK00334 provides a 3:4 ratio. Both are non-PLL fanout buffers in the same family with the same input and output support."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/texas-instruments/LMK00338RTAR","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/texas-instruments/LMK00338RTAR 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}}