ISOW1432: ISOW1432BDFMR

Part Number: ISOW1432

Tool/software:

Hello TI Support,

We are using ISOW1432BDFMR in an isolated RS-485 interface and are observing higher-than-expected noise. Could you help review our setup?

  • Hi Vijayalakshmi,

    Thanks for reaching out.

    I request you to be specific in stating your issue - is it the noise on supply, Bus Lines, D/R  or is it something else? Also please attach a scope shot/result for us to review the noise levels and comment better.

    In the mean time, I have a few comments on the schematic above:

    1. There are no Decoupling Capacitor on VDD - Just like VISOOUT, VDD also needs 10nF+1uF+10uF Capacitor, not having this can affect the device performance considerably
    2. Please make sure the layout guidelines mentioned in datasheet are strictly followed in your PCB.

    Regards
    Varun