{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"LTC3857EUH#TRPBF","brand":"Analog Devices","brandSlug":"analog-devices","productSlug":"LTC3857EUHTRPBF","canonicalUrl":"https://icboms.com/analog-devices/LTC3857EUHTRPBF","factsUrl":"https://icboms.com/api/mcp/products/LTC3857EUH%23TRPBF","rawCanonicalId":null},"summary":{"shortDescription":"Analog Devices LTC3857EUH#TRPBF, PolyPhase series, IC REG CTRLR BUCK 32QFN, 2-output step-down controller, 4V to 38V supply, 105kHz–835kHz switching, synchronous rectification, -40°C to 125°C, 32-WFQFN exposed pad.","salesMarkdown":"## 2-phase buck controller for high-current rails The LTC3857EUH#TRPBF is a PolyPhase step-down switching regulator controller from Analog Devices, designed to drive two independent synchronous buck channels with interleaved phase timing. It operates from a 4V to 38V supply rail and delivers a positive output configuration with up to 99.4% duty cycle, making it suitable for intermediate bus conversion and high-current point-of-load regulation in industrial, automotive, and telecom equipment. ## Switching frequency and inductor sizing The switching frequency is programmable across two ranges: 105kHz to 835kHz and 350kHz to 535kHz. The lower range suits designs prioritising efficiency and thermal margin; the upper range shrinks the magnetics but increases switching losses. The wide spread lets you balance inductor size against dissipation without changing the controller. ## Synchronous rectification and duty cycle headroom Synchronous rectification is built in, so the external low-side FET replaces the catch diode — expect efficiency gains above 90% at moderate loads. The 99.4% maximum duty cycle keeps the output regulated through input sags, useful when the supply bus droops during cranking or brownout. ## Control features for sequencing and fault handling The controller integrates current limit, enable, frequency control, phase control, power good, soft start, and output tracking. Phase control lets you set the interleaving angle between the two channels, reducing input ripple current. Power good and tracking simplify rail sequencing in multi-voltage designs. ## Package and thermal considerations Housed in a 32-WFQFN with exposed pad (5x5 mm), the part relies on the PCB land pattern and via array under the pad to pull heat out of the junction. The operating junction temperature range is -40°C to 125°C, covering industrial and automotive under-hood environments. Surface-mount assembly is standard; the exposed pad must be soldered to a thermal plane. ## Lifecycle and sourcing The LTC3857EUH#TRPBF is listed as Active with ROHS3 compliance.","metaTitle":"LTC3857EUH#TRPBF PolyPhase Buck Controller, 2-Phase, 4-38V","metaDescription":"LTC3857EUH#TRPBF is an active PolyPhase step-down controller with 2 outputs, synchronous rectification, 105kHz–835kHz switching, -40°C to 125°C.","metaKeywords":null},"attributes":{"series":"PolyPhase®","packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Analog & Data Acquisition"],"specifications":{"Series":"PolyPhase®","Package":"Tape & Reel (TR); Cut Tape (CT)","Function":"Step-Down","Topology":"Buck","Clock Sync":"No","Output Type":"Transistor Driver","Mounting Type":"Surface Mount","Output Phases":"2","Package / Case":"32-WFQFN Exposed Pad","lifecycle_stage":"eol_hot","Control Features":"Current Limit, Enable, Frequency Control, Phase Control, Power Good, Soft Start, Tracking","Duty Cycle (Max)":"99.4%","Number of Outputs":"2","Output Configuration":"Positive","Frequency - Switching":"105kHz ~ 835kHz, 350kHz ~ 535kHz","Operating Temperature":"-40°C ~ 125°C (TJ)","Synchronous Rectifier":"Yes","Supplier Device Package":"32-QFN (5x5)","Voltage - Supply (Vcc/Vdd)":"4V ~ 38V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$12.06","stockQuantity":0,"priceTiers":[{"qty":1,"price":"$12.06000","currency":"USD"},{"qty":10,"price":"$10.89400","currency":"USD"},{"qty":25,"price":"$10.38680","currency":"USD"},{"qty":100,"price":"$9.01890","currency":"USD"},{"qty":250,"price":"$8.61356","currency":"USD"},{"qty":500,"price":"$7.85354","currency":"USD"},{"qty":1000,"price":"$7.17000","currency":"USD"},{"qty":2500,"price":"$7.17000","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/694c9c6b7bdd5713a79342bb3fa87e8f.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What is the operating temperature and voltage range of LTC3857EUH#TRPBF?","answer":"The supply voltage (Vcc/Vdd) range is 4V to 38V, and the operating junction temperature range is -40°C to 125°C."},{"question":"Can I use LTC3857EUH#TRPBF in a 2-phase buck converter design?","answer":"Yes, this part is specifically a 2-output, 2-phase step-down controller. The two channels can be paralleled with interleaved phase timing for reduced input ripple and higher output current."},{"question":"What is the switching frequency range of LTC3857EUH#TRPBF?","answer":"The switching frequency is programmable from 105kHz to 835kHz, with a secondary range of 350kHz to 535kHz."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/analog-devices/LTC3857EUHTRPBF","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/analog-devices/LTC3857EUHTRPBF 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}}