{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"LTC3789EUFD#PBF","brand":"Analog Devices","brandSlug":"analog-devices","productSlug":"LTC3789EUFDPBF","canonicalUrl":"https://icboms.com/analog-devices/LTC3789EUFDPBF","factsUrl":"https://icboms.com/api/mcp/products/LTC3789EUFD%23PBF","rawCanonicalId":null},"summary":{"shortDescription":"Analog Devices LTC3789EUFD#PBF, a step-up/step-down switching regulator controller in 28-QFN, buck-boost topology, 4V to 38V supply, 200kHz to 640kHz switching, synchronous rectification, -40°C to 125°C junction temperature.","salesMarkdown":"## Buck-boost controller with synchronous rectification The LTC3789EUFD#PBF is a current-mode buck-boost controller that regulates a positive output voltage from an input that can be above, below, or equal to the output. It drives two sets of external N-channel MOSFETs — one pair for the buck stage, one for the boost stage — and integrates the synchronous rectifier drivers so you skip the catch diode entirely. Supply range is 4V to 38V (Vcc/Vdd), which covers 12V and 24V industrial rails, automotive battery lines through crank and load-dump, and battery-backed systems from 4-cell Li-ion up. Switching frequency is programmable from 200kHz to 640kHz via a single resistor on the RT pin — no external clock sync. Higher frequencies shrink the inductor and output capacitor, lower frequencies improve efficiency at heavy load. ## Thermal and package constraints for the layout The 28-QFN (4x5 mm) exposed pad package requires a solid thermal connection to the PCB ground plane. The pad is the primary heat path — without a via array under the pad the junction temperature rises quickly above 85°C ambient at full load. The limiting factor becomes the MOSFETs and inductor — their temperature ratings set the real ceiling. ## Control features that simplify the BOM On-chip control features include current limit, enable, frequency control, power good, and soft start. The soft-start pin lets you ramp the output voltage gradually, preventing inrush current from tripping the upstream supply. Maximum duty cycle is 90%, which limits the step-down ratio at low input voltages. For a 5V output from a 6V input, the 90% ceiling is comfortable — but a 3.3V output from a 4V input pushes the duty cycle close to the limit, leaving little margin for transient drop. ## Active production — sourcing via RFQ Surface-mount 28-QFN (4x5 mm). Sourced per RFQ against your BOM quantity — no stock-holding claim, no firm lead time quoted on page.","metaTitle":"LTC3789EUFD#PBF Buck-Boost Controller – 4V–38V, 28-QFN","metaDescription":"Analog Devices LTC3789EUFD#PBF step-up/step-down switching regulator controller.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Sensors & Transducers"],"specifications":{"Package":"Tube","Function":"Step-Up/Step-Down","Topology":"Buck-Boost","Clock Sync":"No","Output Type":"Transistor Driver","Mounting Type":"Surface Mount","Output Phases":"1","Package / Case":"28-WFQFN Exposed Pad","lifecycle_stage":"eol_hot","Control Features":"Current Limit, Enable, Frequency Control, Power Good, Soft Start","Duty Cycle (Max)":"90%","Number of Outputs":"2","Output Configuration":"Positive","Frequency - Switching":"200kHz ~ 640kHz","Operating Temperature":"-40°C ~ 125°C (TJ)","Synchronous Rectifier":"Yes","Supplier Device Package":"28-QFN (4x5)","Voltage - Supply (Vcc/Vdd)":"4V ~ 38V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$11.88","stockQuantity":0,"priceTiers":[{"qty":1,"price":"$11.88000","currency":"USD"},{"qty":10,"price":"$10.91600","currency":"USD"},{"qty":25,"price":"$10.46360","currency":"USD"},{"qty":100,"price":"$9.21930","currency":"USD"},{"qty":250,"price":"$8.76680","currency":"USD"},{"qty":500,"price":"$8.20120","currency":"USD"},{"qty":1000,"price":"$7.52248","currency":"USD"}]},"links":{"datasheetUrl":"https://www.analog.com/media/en/technical-documentation/data-sheets/3789fc.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What is the difference between LTC3789EUFD#PBF and the LTC3786IUD#PBF?","answer":"The LTC3786 is a single-output boost/flyback/SEPIC controller with a 96% max duty cycle and a 105 kHz switching frequency. The LTC3789 is a dual-output buck-boost controller with a 200 kHz–640 kHz range and 90% duty cycle. The LTC3789 handles step-up/step-down regulation in one stage; the LTC3786 is for step-up-only topologies."},{"question":"What package does LTC3789EUFD#PBF come in?","answer":"28-lead WFQFN with exposed pad, 4x5 mm body. Supplied in Tube."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/analog-devices/LTC3789EUFDPBF","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/analog-devices/LTC3789EUFDPBF 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}}