TheADuM3400/ADuM3401/ADuM3402are 4-channel digital isolators based on the Analog Devices, Inc.,iCoupler®technology. Combining high speed CMOS and monolithic air core transformer technology, these isolation components provide outstanding performance characteristics superior to alternatives such as optocoupler devices.iCoupler devices remove the design difficulties commonly associated with optocouplers. Typical optocoupler concerns regarding uncertain current transfer ratios, nonlinear transfer functions, and temperature and lifetime effects are eliminated with the simpleiCoupler digital interfaces and stable performance characteristics. The need for external drivers and other discrete components is eliminated with theseiCoupler products. Furthermore,iCoupler devices consume one-tenth to one-sixth the power of optocouplers at comparable signal data rates.The isolators provide four independent isolation channels in a variety of channel configurations and data rates (see the Ordering Guide). All models operate with the supply voltage on either side ranging from 2.7 V to 5.5 V, providing compatibility with lower voltage systems as well as enabling a voltage translation functionality across the isolation barrier. The isolators have a patented refresh feature that ensures dc correctness in the absence of input logic transitions and during powerup/power-down conditions.In comparison to theADuM1400/ADuM1401/ADuM1402isolators, the ADuM3400/ADuM3401/ADuM3402 isolators contain various circuit and layout changes to provide increased capability relative to system-level IEC 61000-4-x testing (ESD/ burst/surge). The precise capability in these tests for either set of isolators is strongly determined by the design and layout of the user’s board or module. For more information, see the AN-793 application note,ESD/Latch-Up Considerations withiCoupler Isolation Products.ApplicationsGeneral-purpose multichannel isolationSPI/data converter isolationRS-232/RS-422/RS-485 transceiversIndustrial field bus isolation