{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"LTC3866EUF#PBF","brand":"Analog Devices","brandSlug":"analog-devices","productSlug":"LTC3866EUF~4PBF","canonicalUrl":"https://icboms.com/analog-devices/LTC3866EUF~4PBF","factsUrl":"https://icboms.com/api/mcp/products/LTC3866EUF%23PBF","rawCanonicalId":null},"summary":{"shortDescription":"Analog Devices LTC3866EUF#PBF step-down synchronous buck controller, 4.5V-38V supply, 250kHz-770kHz switching, transistor driver output, 24-WFQFN exposed pad, tube.","salesMarkdown":"## Buck controller with synchronous rectification The LTC3866EUF#PBF: The synchronous rectifier improves efficiency by replacing the freewheeling diode with a second FET, cutting conduction losses in the low-side path — important for high-current POL rails where every millivolt of dropout costs thermal headroom. It operates from a 4.5V to 38V supply (Vcc/Vdd), which covers common intermediate bus rails (5V, 12V, 24V) and industrial supplies up to 36V nominal. The switching frequency is programmable from 250kHz to 770kHz via a resistor on the RT pin — lower frequency cuts switching losses for heavy loads; higher frequency shrinks the inductor and output cap but pushes more loss into the FET gate drive. The controller outputs a transistor driver signal — it does not integrate the power FETs, so the external MOSFET pair must be selected for the target load current and input voltage. ## Control features and rework note The LTC3866EUF#PBF includes current limit, enable, frequency control, power good, soft start, and tracking. The tracking feature allows the output to follow an external reference ramp during startup — useful for sequencing multiple rails in an FPGA or ASIC power tree where the core must not rise before the I/O. Soft start limits inrush current; the power-good flag can drive a reset or enable the next converter in the sequence. The 24-QFN (4x4 mm) is a standard QFN with a centre pad — the pad is the main thermal path and the ground return for the gate-drive loop. The pin 1 corner is marked by a chamfer on the package body, visible under a microscope. The exposed pad sits flush with the bottom of the package; a stencil aperture of 50-60% of the pad area keeps solder from wicking up the sides and shorting to the thermal land vias. The part is ROHS3 compliant, so the solder balls are lead-free — reflow profile follows the standard SAC305 curve with a peak around 245°C.","metaTitle":"LTC3866EUF#PBF Buck Controller, 4.5-38V, 24-QFN","metaDescription":"Active LTC3866EUF#PBF step-down buck controller from Analog Devices. 4.5V-38V supply, 250kHz-770kHz switching, -40°C to +125°C. 24-QFN. Quoted to order.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Analog & Data Acquisition"],"specifications":{"Package":"Tube","Function":"Step-Down","Topology":"Buck","Clock Sync":"No","Output Type":"Transistor Driver","Mounting Type":"Surface Mount","Output Phases":"1","Package / Case":"24-WFQFN Exposed Pad","lifecycle_stage":"eol_hot","Control Features":"Current Limit, Enable, Frequency Control, Power Good, Soft Start, Tracking","Number of Outputs":"1","Output Configuration":"Positive","Frequency - Switching":"250kHz ~ 770kHz","Operating Temperature":"-40°C ~ 125°C (TJ)","Synchronous Rectifier":"Yes","Supplier Device Package":"24-QFN (4x4)","Voltage - Supply (Vcc/Vdd)":"4.5V ~ 38V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$8.22","stockQuantity":0,"priceTiers":[{"qty":1,"price":"$8.22000","currency":"USD"},{"qty":10,"price":"$7.43000","currency":"USD"},{"qty":25,"price":"$7.08400","currency":"USD"},{"qty":100,"price":"$6.15100","currency":"USD"},{"qty":250,"price":"$5.87452","currency":"USD"},{"qty":500,"price":"$5.35618","currency":"USD"},{"qty":1000,"price":"$4.89000","currency":"USD"}]},"links":{"datasheetUrl":null,"sourceUrl":null},"ai":{"faq":[{"question":"What is the difference between LTC3866EUF#PBF and LTC3866EUF#TRPBF?","answer":"The LTC3866EUF#PBF ships in a tube, while the LTC3866EUF#TRPBF is the same device in tape-and-reel packaging. The electrical specifications, package (24-QFN), and pinout are identical — the only difference is the shipping medium, so the TRPBF variant is the pick-and-place friendly version for automated assembly."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/analog-devices/LTC3866EUF~4PBF","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/analog-devices/LTC3866EUF~4PBF 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}}