{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"LT1243CN8#PBF","brand":"Analog Devices","brandSlug":"analog-devices","productSlug":"LT1243CN8PBF","canonicalUrl":"https://icboms.com/analog-devices/LT1243CN8PBF","factsUrl":"https://icboms.com/api/mcp/products/LT1243CN8%23PBF","rawCanonicalId":null},"summary":{"shortDescription":"Analog Devices LT1243CN8#PBF, Buck PWM Controller, Step-Down Topology, 500 kHz Switching Frequency, 96% Max Duty Cycle, 8.2V to 25V Supply, 8-PDIP Through Hole, Tube.","salesMarkdown":"## Buck controller in an 8-pin DIP — what it is and where it fits The LT1243CN8#PBF is a current-mode PWM buck controller from Analog Devices, designed for step-down (buck) converter applications. It drives an external transistor switch at a fixed 500 kHz switching frequency, with a maximum duty cycle of 96% — useful when the input-to-output differential is small. The controller operates from an 8.2 V to 25 V supply rail and delivers a single positive output that can be configured for isolated designs. Housed in an 8-lead PDIP (0.300\" width, 7.62 mm pitch), it is a through-hole part suited for benchtop prototypes, low-to-medium volume production, or legacy board repairs where surface-mount rework is impractical. ## 500 kHz switching — what it means for your magnetics and BOM Switching at 500 kHz reduces inductor and capacitor size. The controller lacks a clock-sync pin, so it runs free. ## 96% duty cycle — low-dropout capability A 96% maximum duty cycle allows the output to stay regulated when the input is close to the output voltage. ## Temperature grade and environment Junction temperature range is 0°C to 100°C, suitable for commercial indoor equipment. ## Lifecycle and sourcing The LT1243CN8#PBF is listed as Active by the manufacturer — no end-of-life notice, no last-time-buy window. It is a current-production part available through independent distribution. For BOM planning, there is no LTB risk on this line.","metaTitle":"LT1243CN8#PBF Buck Controller IC, 500 kHz, 96% Duty Cycle","metaDescription":"LT1243CN8#PBF is an active buck controller IC from Analog Devices. Switching frequency 500 kHz, max duty cycle 96%, 8.2V-25V supply, 8-PDIP.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Analog & Data Acquisition"],"specifications":{"Package":"Tube","Function":"Step-Down","Topology":"Buck","Clock Sync":"No","Output Type":"Transistor Driver","Mounting Type":"Through Hole","Output Phases":"1","Package / Case":"8-DIP (0.300\\\", 7.62mm)","lifecycle_stage":"eol_hot","Control Features":"Frequency Control","Duty Cycle (Max)":"96%","Number of Outputs":"1","Output Configuration":"Positive, Isolation Capable","Frequency - Switching":"500kHz","Operating Temperature":"0°C ~ 100°C (TJ)","Synchronous Rectifier":"No","Supplier Device Package":"8-PDIP","Voltage - Supply (Vcc/Vdd)":"8.2V ~ 25V"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$6.58","stockQuantity":0,"priceTiers":[{"qty":1,"price":"$6.58000","currency":"USD"},{"qty":10,"price":"$5.94800","currency":"USD"},{"qty":25,"price":"$5.67160","currency":"USD"},{"qty":100,"price":"$4.92450","currency":"USD"},{"qty":250,"price":"$4.70320","currency":"USD"},{"qty":500,"price":"$4.28824","currency":"USD"},{"qty":1000,"price":"$3.91500","currency":"USD"}]},"links":{"datasheetUrl":"https://www.analog.com/media/en/technical-documentation/data-sheets/lt1241.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What is the maximum duty cycle of LT1243CN8#PBF?","answer":"The maximum duty cycle is 96%, which allows low-dropout operation when the input voltage is close to the output voltage."},{"question":"What is the switching frequency of LT1243CN8#PBF?","answer":"The switching frequency is fixed at 500 kHz. There is no clock synchronization input."},{"question":"How does LT1243CN8#PBF compare to UC3843?","answer":"Both are current-mode PWM controllers, but the LT1243CN8#PBF operates at 500 kHz and offers a 96% duty cycle, while the UC3843 typically runs at lower frequencies and has a lower maximum duty cycle. The LT1243 is designed for buck topologies; the UC3843 is more commonly used in flyback and boost converters. Direct substitution requires checking the pinout and compensation network."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/analog-devices/LT1243CN8PBF","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/analog-devices/LT1243CN8PBF 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}}