{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"ISO7731BDW","brand":"Texas Instruments","brandSlug":"texas-instruments","productSlug":"ISO7731BDW","canonicalUrl":"https://icboms.com/texas-instruments/ISO7731BDW","factsUrl":"https://icboms.com/api/mcp/products/ISO7731BDW","rawCanonicalId":null},"summary":{"shortDescription":"Texas Instruments ISO7731BDW, General Purpose digital isolator, Capacitive Coupling, 3-channel unidirectional, 100 Mbps data rate, 5000 Vrms isolation, 2.25 V ~ 5.5 V supply, -55°C ~ 125°C, 16-SOIC package.","salesMarkdown":"## Isolation barrier and speed — what 5000 Vrms and 100 Mbps mean for the design The Texas Instruments ISO7731BDW is a three-channel, unidirectional digital isolator using capacitive coupling technology. It provides reinforced isolation rated at 5000 Vrms, making it suitable for applications requiring a robust safety barrier, such as industrial motor drives, grid-tied inverters, and medical equipment where galvanic isolation between high-voltage and low-voltage domains is mandatory. With a data rate of 100 Mbps and propagation delays of 16 ns max in both directions, this part handles high-speed digital signals like SPI, UART, or CAN without introducing significant timing skew. The 1.3 ns typical rise/fall times keep signal edges clean enough to avoid excessive EMI, but the fast edges also mean the layout needs care — keep the isolation barrier clear of noisy traces and place the supply decoupling close to the pins. The 85 kV/µs minimum common-mode transient immunity (CMTI) ensures the output does not glitch when a fast voltage transient slams across the isolation barrier — a key spec for systems with SiC or GaN switching stages where dv/dt can exceed 50 V/ns. If the power stage runs slower (IGBTs at a few kHz), the margin is generous; the CMTI number matters most when the switching edge is sharp. ## Supply rails and channel configuration The ISO7731BDW operates from 2.25 V to 5.5 V on both sides, so it can bridge a 3.3 V MCU domain to a 5 V peripheral or sensor interface without a level shifter. The supply range also covers 1.8 V logic at the low end (though 2.25 V minimum means 1.8 V logic needs a translator), and 5 V tolerant inputs on the high side. Channel assignment is 2 inputs on side 1, 1 input on side 2 — unidirectional only. That is a common configuration for isolating a two-wire SPI (SCLK, MOSI) from the controller side and a single MISO feedback line from the peripheral. If bidirectional signals (e.g., I²C SDA) are needed, this part does not support them; a different isolator with directional control or a dedicated I²C isolator would be required. ## Temperature range and package — environment fit The 16-SOIC wide-body (7.50 mm width) package provides the creepage distance needed to maintain the 5000 Vrms isolation rating across the PCB — standard SOIC-8 narrow-body would not meet the clearance. MSL 3 applies; if the moisture-barrier bag has been open longer than the floor life, bake before reflow.","metaTitle":"TI ISO7731BDW Digital Isolator, 5000 Vrms, 100 Mbps, 16-SOIC","metaDescription":"Texas Instruments ISO7731BDW general-purpose digital isolator: 5000 Vrms isolation, 100 Mbps data rate, 3 unidirectional channels, -55°C to 125°C.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Digital Isolators"],"specifications":{"Mfr":"Texas Instruments","Type":"General Purpose","Series":"-","Package":"Tube","Data Rate":"100Mbps","Technology":"Capacitive Coupling","Channel Type":"Unidirectional","Mounting Type":"Surface Mount","Isolated Power":"No","Package / Case":"16-SOIC (0.295\\\", 7.50mm Width)","Product Status":"Active","lifecycle_stage":"eol_hot","Voltage - Supply":"2.25V ~ 5.5V","Number of Channels":"3","Base Product Number":"ISO7731","Voltage - Isolation":"5000Vrms","Operating Temperature":"-55°C~125°C","Inputs - Side 1/Side 2":"2/1","Rise / Fall Time (Typ)":"1.3ns, 1.4ns","Supplier Device Package":"16-SOIC","Pulse Width Distortion (Max)":"4.9ns","Propagation Delay tpLH / tpHL (Max)":"16ns, 16ns","Common Mode Transient Immunity (Min)":"85kV/µs"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$3.2000","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/5d6896211321d4045592a9dcb13e3d0c.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What is the closest pin-compatible alternative to ISO7731BDW?","answer":"Within the same family, the ISO7731FBDW is a functional equivalent with the same pinout, package, and isolation rating but offers fail-safe high output on the default state. The base product number ISO7731 covers multiple variants differing by output default state (high or low) and supply voltage range — all share the same 16-SOIC footprint. For a drop-in replacement with different channel direction, the ISO7741 series provides four channels with selectable direction, though it is not pin-compatible without layout changes."},{"question":"Does ISO7731BDW support unidirectional or bidirectional channels?","answer":"All three channels are unidirectional. Side 1 has two inputs, side 2 has one input. This part cannot be used for bidirectional signals like I²C without external direction control logic."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/texas-instruments/ISO7731BDW","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/texas-instruments/ISO7731BDW 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}}