{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"UC3842D8TR","brand":"Texas Instruments","brandSlug":"texas-instruments","productSlug":"UC3842D8TR","canonicalUrl":"https://icboms.com/texas-instruments/UC3842D8TR","factsUrl":"https://icboms.com/api/mcp/products/UC3842D8TR","rawCanonicalId":null},"summary":{"shortDescription":"Texas Instruments UC3842D8TR, current-mode PWM controller, 8-SOIC package, switching frequency up to 500 kHz, 97% max duty cycle, 12 V to 28 V supply.","salesMarkdown":"## Current-mode PWM controller for isolated and non-isolated supplies The UC3842D8TR is a fixed-frequency current-mode PWM controller from Texas Instruments, designed for step-up, step-down, step-up/step-down topologies including boost, buck, buck-boost, flyback, and forward converters. It drives a single transistor output with a maximum duty cycle of 97%, which is critical for maintaining regulation in high step-ratio flyback designs where the off-time must be short. Switching frequency reaches up to 500 kHz, allowing the use of smaller magnetics and reducing the overall power-stage footprint — a direct trade-off against switching losses in the MOSFET and snubber network. The controller operates from a 12 V to 28 V supply (Vcc/Vdd), which sets the bias rail headroom. The internal undervoltage lockout (UVLO) thresholds are tied to this range — a supply below 12 V may not reliably start the oscillator. Output configuration is positive and isolation-capable, meaning the controller can drive a primary-side MOSFET in an isolated flyback while the secondary-side feedback loop crosses the isolation barrier via an optocoupler. ## Package format and sourcing posture Housed in an 8-SOIC (0.154\", 3.90 mm width) surface-mount package, supplied on Tape & Reel (TR) or Cut Tape (CT). ROHS3 compliant.","metaTitle":"UC3842D8TR PWM Controller IC – Texas Instruments, 8-SOIC","metaDescription":"UC3842D8TR current-mode PWM controller from TI. Active lifecycle, 8-SOIC, up to 500 kHz, 97% duty cycle. Sourced per RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Power Management (PMIC / Gate Driver)"],"specifications":{"Mfr":"Texas Instruments","Series":"-","Package":"Tape & Reel (TR); Cut Tape (CT)","Function":"Step-Up, Step-Down, Step-Up/Step-Down","Topology":"Boost, Buck, Buck-Boost, Flyback, Forward","Clock Sync":"No","Output Type":"Transistor Driver","Mounting Type":"Surface Mount","Output Phases":"1","Package / Case":"8-SOIC (0.154\\\", 3.90mm Width)","Product Status":"Active","lifecycle_stage":"eol_hot","Control Features":"Frequency Control","Duty Cycle (Max)":"97%","Number of Outputs":"1","Serial Interfaces":"-","Base Product Number":"UC3842","Output Configuration":"Positive, Isolation Capable","Frequency - Switching":"Up to 500kHz","Operating Temperature":"0°C~70°C(TA)","Synchronous Rectifier":"No","Supplier Device Package":"8-SOIC","Voltage - Supply (Vcc/Vdd)":"12V ~ 28V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$1.3600","priceTiers":[{"qty":1,"price":"$1.36000","currency":"USD"},{"qty":10,"price":"$1.21600","currency":"USD"},{"qty":25,"price":"$1.15440","currency":"USD"},{"qty":100,"price":"$0.94840","currency":"USD"},{"qty":250,"price":"$0.88652","currency":"USD"},{"qty":500,"price":"$0.78344","currency":"USD"},{"qty":1000,"price":"$0.61851","currency":"USD"},{"qty":2500,"price":"$0.58350","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/3edad1712993fb3b1751953d793dcfb6.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/UC3842D8TR/alternatives.json"},"ai":{"faq":[{"question":"Can UC3842D8TR be used in a flyback converter?","answer":"Yes, the UC3842D8TR is specified for flyback topology. The 97% maximum duty cycle is particularly useful in flyback designs where the input voltage is low and the output voltage is high, requiring a long on-time relative to the switching period."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/texas-instruments/UC3842D8TR","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/texas-instruments/UC3842D8TR 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}}