{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"UC3846DW","brand":"Texas Instruments","brandSlug":"texas-instruments","productSlug":"UC3846DW","canonicalUrl":"https://icboms.com/texas-instruments/UC3846DW","factsUrl":"https://icboms.com/api/mcp/products/UC3846DW","rawCanonicalId":null},"summary":{"shortDescription":"Texas Instruments UC3846DW current-mode PWM controller, 500 kHz switching, Boost/Flyback/Forward/Half-Bridge/Push-Pull topologies, 16-SOIC wide-body package, tube.","salesMarkdown":"## Switching frequency and topology reach The UC3846DW switches at up to 500 kHz, which sets the practical upper bound for transformer size reduction in isolated designs. At that frequency, the core cross-section shrinks, but the switching losses in the external FETs and the transformer leakage inductance become the limiting factor — not the controller itself. The device supports Boost, Flyback, Forward Converter, Half-Bridge, and Push-Pull topologies, so a single controller BOM line can serve multiple isolated and non-isolated architectures across different board designs. The 50% maximum duty cycle is inherent to the current-mode architecture — it prevents subharmonic oscillation at duty cycles above 50% without external slope compensation. For designs that need >50% duty (e.g., a wide-input Flyback at low line), the designer must move to a push-pull or half-bridge topology where the two outputs interleave to effectively double the on-time per switching period. ## Supply range and control features — what the ratings actually mean for the rail The 6.95 V to 40 V supply range covers the common industrial and telecom rails: a 12 V bus (nominal 13.8 V in a vehicle, 12.0 V in a panel) sits comfortably in the middle, and a 36 V telecom rail stays under the 40 V absolute maximum with a few volts of headroom. The undervoltage lockout threshold is 6.95 V minimum — if the input rail droops below that during a brownout, the controller shuts down cleanly rather than running the external FETs into linear mode. Integrated control features include Current Limit, Enable, Frequency Control, and Soft Start. The current-limit comparator senses the primary-side current through an external sense resistor — the cycle-by-cycle limit protects the power stage during startup or overload without relying on a slow fuse. The Soft Start pin ramps the reference voltage, so the output rises monotonically without overshoot. Frequency Control allows the oscillator to be synchronized to an external clock via the Clock Sync pin, which is useful when multiple converters must share a switching frequency to avoid beat-frequency noise on the input bus. ## Temperature grade and package — board-fit considerations The package is a 16-SOIC wide-body (0.295″ body width, 7.50 mm). That is the wider SOIC-16 footprint, not the narrow 3.9 mm version — the pad layout is different, and a narrow-SOIC footprint will not fit the wide body.","metaTitle":"Texas Instruments UC3846DW PWM Controller, 500kHz, 16-SOIC","metaDescription":"Active-production current-mode PWM controller from TI. 500kHz switching, multiple isolated topologies, 6.95-40V supply. 16-SOIC wide-body. ROHS3.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Discrete Semiconductors"],"specifications":{"Package":"Tube","Function":"Step-Up, Step-Up/Step-Down","Topology":"Boost, Flyback, Forward Converter, Half-Bridge, Push-Pull","Clock Sync":"Yes","Output Type":"Transistor Driver","Mounting Type":"Surface Mount","Output Phases":"1","Package / Case":"16-SOIC (0.295\\\", 7.50mm Width)","lifecycle_stage":"eol_hot","Control Features":"Current Limit, Enable, Frequency Control, Soft Start","Duty Cycle (Max)":"50%","Number of Outputs":"2","Output Configuration":"Positive","Frequency - Switching":"500kHz","Operating Temperature":"0°C ~ 70°C (TA)","Synchronous Rectifier":"Yes","Supplier Device Package":"16-SOIC","Voltage - Supply (Vcc/Vdd)":"6.95V ~ 40V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$4.58","stockQuantity":0,"priceTiers":[{"qty":1,"price":"$4.58000","currency":"USD"},{"qty":10,"price":"$4.11500","currency":"USD"},{"qty":25,"price":"$3.89000","currency":"USD"},{"qty":100,"price":"$3.37130","currency":"USD"},{"qty":250,"price":"$3.19840","currency":"USD"},{"qty":500,"price":"$2.86990","currency":"USD"},{"qty":1000,"price":"$2.44650","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/368655a34305c4e331930629d8ba0153.pdf","sourceUrl":null},"ai":{"faq":[{"question":"Will the UC3846DW drop into a board designed for the UCC2806DWTR?","answer":"The UC3846DW and UCC2806DWTR share the same pinout and 16-SOIC wide-body package, so a board designed for one will physically accept the other. The functional difference is that the UC3846DW includes a Clock Sync pin and a wider topology set including Half-Bridge and Push-Pull, while the UCC2806DWTR lacks clock sync and is limited to Boost, Flyback, and Forward. The supply range and current-limit architecture are similar, but the compensation network may need tuning for the different oscillator characteristics — confirm the loop response before committing."},{"question":"What compliance documentation is available for the UC3846DW?","answer":"The UC3846DW is ROHS3 compliant, which means it meets the EU RoHS directive without any exempted substances. Texas Instruments provides the standard compliance documentation — RoHS certificates of compliance and material declaration reports are available through their compliance portal."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/texas-instruments/UC3846DW","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/texas-instruments/UC3846DW 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}}