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ISOW1412: 5V↔︎3.3V level conversion communication with ISOW1412

Part Number: ISOW1412


I am currently planning to use the ISOW1412 for communication between the MCU and the external board.
Is it possible to communicate between MCU (3.3V) and external board (5V) using ISOW1412?
Or when using the ISOW1412, do I need to drive the MCU side with 5V?



  • Hi Astro,

    Thanks for reaching out.

    As stated in the datasheet, the voltages supported by VDD and VIO are listed as below and they can be set independent of each other. If your MCU is powered by 3.3V then VIO of ISOW1412 should be set to 3.3V and all the logic I/O pins on side1 of ISOW1412 will be operating at 3.3V. The VDD can be independently be at 3.3V or 5V irrespective of VIO.

    The VDD and VISOOUT can be used in 3 configurations, as listed below and also shown in the Supply Configuration Function Table in the datasheet.

    1. VDD = 5V, VISOOUT = 5V
    2. VDD = 5V, VISOOUT = 3.3V
    3. VDD = 3.3V, VISOOUT = 3.3V
    4. VDD = 3.3V, VISOOUT = 3.3V - this is an invalid configuration and not supported by device.

    Koteshwar Rao