{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"UC3843ADG4","brand":"Texas Instruments","brandSlug":"texas-instruments","productSlug":"UC3843ADG4","canonicalUrl":"https://icboms.com/texas-instruments/UC3843ADG4","factsUrl":"https://icboms.com/api/mcp/products/UC3843ADG4","rawCanonicalId":null},"summary":{"shortDescription":"Texas Instruments UC3843ADG4 current-mode PWM controller, Boost/Buck/Flyback/Forward topology, up to 500 kHz, 96% max duty cycle, 7.6 V to 30 V supply, 14-SOIC, 0°C to 70°C.","salesMarkdown":"The UC3843ADG4: The Vcc supply range of 7.6 V to 30 V covers the bias rail for most offline and telecom-derived supplies. The 96% maximum duty cycle allows the controller to maintain regulation through deep step-down ratios in a buck or high step-up in a boost or flyback without skipping pulses. Switching frequency is rated up to 500 kHz, which lets the designer shrink the magnetic components — the trade-off is higher switching losses in the MOSFET and rectifier, so the frequency choice is a thermal budget decision, not a raw speed target. ## Temperature grade and package — fit for commercial equipment ## Topology flexibility — one controller, multiple converter types The UC3843ADG4 supports boost, buck, flyback, and forward topologies. The single transistor-driver output with positive, isolation-capable configuration means it can drive the primary-side MOSFET in an isolated flyback or forward converter directly, or the high-side switch in a non-isolated buck. The frequency-control feature gives the designer a single resistor to set the oscillator timing, simplifying the BOM.","metaTitle":"Texas Instruments UC3843ADG4 PWM Controller, 500 kHz","metaDescription":"UC3843ADG4 current-mode PWM controller from TI. Boost/buck/flyback/forward topology, up to 500 kHz, 96% duty cycle, 14-SOIC.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Power Management (PMIC / Gate Driver)"],"specifications":{"Mfr":"Texas Instruments","Series":"-","Package":"Tube","Function":"Step-Up, Step-Down, Step-Up/Step-Down","Topology":"Boost, Buck, Flyback, Forward","Clock Sync":"No","Output Type":"Transistor Driver","Mounting Type":"Surface Mount","Output Phases":"1","Package / Case":"14-SOIC (0.154\\\", 3.90mm Width)","lifecycle_stage":"eol_hot","Control Features":"Frequency Control","Duty Cycle (Max)":"96%","Number of Outputs":"1","Serial Interfaces":"-","Base Product Number":"UC3843","Output Configuration":"Positive, Isolation Capable","Frequency - Switching":"Up to 500kHz","Operating Temperature":"0°C~70°C(TA)","Synchronous Rectifier":"No","Supplier Device Package":"14-SOIC","Voltage - Supply (Vcc/Vdd)":"7.6V ~ 30V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$1.2600","priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/3edad1712993fb3b1751953d793dcfb6.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/UC3843ADG4/alternatives.json"},"ai":{"faq":[{"question":"Can UC3843ADG4 be used in a flyback converter?","answer":"Yes. The UC3843ADG4 is explicitly listed for flyback topology. The 96% duty cycle and single transistor-driver output suit the primary-side switch drive in an isolated flyback. The switching frequency up to 500 kHz allows a compact transformer design."},{"question":"What is the difference between UC3843 and UC3842?","answer":"The primary difference is the undervoltage lockout (UVLO) thresholds. UC3843 has a turn-on threshold of 8.4 V and a turn-off of 7.6 V, while UC3842 has 16 V on / 10 V off. The UC3843 is therefore suited for lower input voltage rails where the 16 V UVLO of the UC3842 would never enable."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/texas-instruments/UC3843ADG4","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/texas-instruments/UC3843ADG4 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-22T18:03:28.771Z","lastPublished":"2026-07-22T18:03:28.771Z","indexable":true}}