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SN6505B: Examples of D1/D2 > 5V

Intellectual 1280 points

Replies: 3

Views: 35

Part Number: SN6505B

Hi team,

My customer wants to use this device with the logic level at 5V and the driver side at 12V. I can't seem to find any examples online that have D1/D2 >5V. I see the abs max for these pins is 16V, but I'm looking for confirmation that this setup is ok.

Thanks,

Michael

  • Hi Michael,

    Thank you for posting to E2E!

    Can you share a schematic of the configuration described above with SN6505? From my understanding, our customer would like to power the SN6505 Vcc, EN, and (if needed) the CLK pin with 5V while powering the center tap of the push-pull transformer with 12V.

    If this is the case, SN6505 will not be able to withstand such operation due to the push-pull topology, which reflects 2x the transformer center-tap voltage on D1 and D2. Thus, for > 5V operation, we recommend a topology like the one shown below:



    Please let us know if this is relevant to our customer's design.


    Thank you,
    Manuel Chavez

  • In reply to Manuel Chavez:

    Hi Manuel,

    Thanks for the quick reply.

    Your understanding of the setup is correct. Is there anything in the datasheet that explains the 2x reflection on the D1/D2 pins? I wasn't able to find it.

    Thanks,

    Michael

  • In reply to Michael Balourdas:

    Hi Michael,

    No worries! The push-pull converter behavior is described in Section 8.3.1, as shown below:




    For a 12V to isolated-12V power supply, the schematic above will suffice. When selecting the FETs, do choose components with low Rds_on, lowest Vgth, and Vgs > 24V.


    Respectfully,
    Manuel Chavez