{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"ISO7631FCDW","brand":"Texas Instruments","brandSlug":"texas-instruments","productSlug":"ISO7631FCDW","canonicalUrl":"https://icboms.com/texas-instruments/ISO7631FCDW","factsUrl":"https://icboms.com/api/mcp/products/ISO7631FCDW","rawCanonicalId":null},"summary":{"shortDescription":"TI ISO7631FCDW general-purpose digital isolator, capacitive coupling, 3 unidirectional channels, 25 Mbps data rate, 2500 Vrms isolation, 3V to 5.5V supply, -40°C to 125°C, 16-SOIC.","salesMarkdown":"## What this 3-channel capacitive isolator covers The TI ISO7631FCDW is a general-purpose digital isolator using capacitive coupling to pass signals across a 2500 Vrms isolation barrier. Its three unidirectional channels — two on side 1, one on side 2 — handle data rates up to 25 Mbps with a typical propagation delay of 28 ns and pulse-width distortion held to 3 ns max. This is the part you reach for when an optocoupler's current transfer ratio drift or LED aging becomes a reliability concern in a medium-speed isolation path — think isolated SPI, UART, or general-purpose GPIO crossing a safety barrier in industrial fieldbus nodes, motor drives, or medical equipment that needs reinforced isolation without the power overhead of a dedicated isolated DC-DC. ## 25 Mbps timing budget — what the 28 ns prop delay buys you At 25 Mbps the bit period is 40 ns, so a 28 ns propagation delay consumes about 70% of the period before the receiver even sees the edge. That leaves roughly 12 ns of timing margin for the rest of the signal path — the driver's output rise/fall (2.8 ns, 2.9 ns typical), PCB trace skew, and the receiver's setup/hold. For a 10 MHz SPI clock the margin is comfortable; pushing toward 25 Mbps means the layout needs controlled impedance and matched trace lengths to avoid losing the setup window. The 3 ns max pulse-width distortion means the on-chip timing skew between the rising and falling edges stays tight — important for PWM signals or any protocol where duty-cycle fidelity matters. If you are isolating a 25 kHz PWM for a motor drive, the distortion adds less than 0.03% duty-cycle error. ## CMTI and isolation — staying alive in a noisy environment Common-mode transient immunity is rated at 25 kV/µs minimum, which is the figure that keeps the output from glitching when a motor-drive IGBT switches a 600 V bus in a few tens of nanoseconds. That transient couples through parasitic capacitance across the isolation barrier; the capacitive coupling technology in this part handles it without the LED-drive current that an optocoupler would need to maintain its CTR. The 2500 Vrms isolation is rated for basic or reinforced isolation per IEC 60747-17, sufficient for mains-connected industrial equipment. At the high end, keep in mind that propagation delay typically increases with temperature — budget an extra 10-15% for timing closure above 85°C. ## Active status and sourcing posture For production BOMs that need a second source, the ISO7420FEDR is a 2-channel unidirectional alternative with a higher 50 Mbps data rate and similar 2500 Vrms isolation — but it drops one channel, so the channel count difference rules it out for a 3-channel design without a board spin.","metaTitle":"TI ISO7631FCDW digital isolator, 3-ch, 25 Mbps, 2500 Vrms","metaDescription":"TI ISO7631FCDW general-purpose digital isolator: 3 unidirectional channels, 25 Mbps data rate, 2500 Vrms isolation, capacitive coupling, -40°C to 125°C","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":"ROHS3 Compliant","productStatus":"Active","categoryPath":["Digital Isolators"],"specifications":{"Type":"General Purpose","Package":"Tube","Data Rate":"25Mbps","Technology":"Capacitive Coupling","Channel Type":"Unidirectional","Mounting Type":"Surface Mount","Isolated Power":"No","Package / Case":"16-SOIC (0.295\\\", 7.50mm Width)","lifecycle_stage":"eol_hot","Voltage - Supply":"3V ~ 5.5V","Number of Channels":"3","Voltage - Isolation":"2500Vrms","Operating Temperature":"-40°C ~ 125°C","Inputs - Side 1/Side 2":"2/1","Rise / Fall Time (Typ)":"2.8ns, 2.9ns","Supplier Device Package":"16-SOIC","Pulse Width Distortion (Max)":"3ns","Propagation Delay tpLH / tpHL (Max)":"28ns, 28ns","Common Mode Transient Immunity (Min)":"25kV/µs"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$5.28","stockQuantity":0,"priceTiers":[{"qty":1,"price":"$5.28000","currency":"USD"},{"qty":10,"price":"$4.74500","currency":"USD"},{"qty":25,"price":"$4.48600","currency":"USD"},{"qty":100,"price":"$3.88800","currency":"USD"},{"qty":250,"price":"$3.68864","currency":"USD"},{"qty":500,"price":"$3.30980","currency":"USD"},{"qty":1000,"price":"$2.82150","currency":"USD"}]},"links":{"datasheetUrl":"https://cdn.icboms.com/bf9cebb440d291e450b6af033fbf97fc.pdf","sourceUrl":null},"ai":{"faq":[{"question":"Is ISO7631FCDW unidirectional or bidirectional?","answer":"All three channels are unidirectional, with two inputs on side 1 and one input on side 2. Data flows in one direction per channel, so this part is suited for isolated SPI (with separate lines for MOSI, MISO, and SCK) or similar unidirectional signal paths."},{"question":"What is the equivalent of ISO7631FCDW?","answer":"The closest functional peer is the ISO7420FEDR, also a TI capacitive-coupling isolator with 2500 Vrms isolation. However, the ISO7420FEDR has only two channels (2/0 input count) and a faster 50 Mbps data rate. Neither is a drop-in replacement — the channel count and package differ."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/texas-instruments/ISO7631FCDW","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/texas-instruments/ISO7631FCDW 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}}