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  • TI Thinks Resolved

DRV8412: PVDD with different supply

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Replies: 8

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Part Number: DRV8412

For the  PVDD_B、PVDD_C, PVDD_D is 12V,but PVDD_A is 5V,GVDD_X and VDD are 12V, will this a problem? For the PVDD A,B,C,D is not the same voltage.  and also how about the PVDD_A is 0V, but others  PVDD are still 12V? thanks

  • Hi Jason,

    Before we can answer your question, can you provide some additional information?

    What is the application?
    What mode will DRV8412 be used? (M3, M2, M1 = ???)
    What is the PWM frequency of the 12V outputs?
    What is the PWM frequency of the 5V output?

    Rick Duncan
    Motor Applications Team

  • In reply to Rick Duncan:

    Hi Jason,

    Do you answers for the questions above?

    Rick Duncan
    Motor Applications Team

  • In reply to Rick Duncan:

    Hi Rick

    Thanks for your help,

    The application is drive the relay and proportional electromagnetic.

    M3,M2,M1 is all zero.

    For 12V output to drive the proportional electromagnetic, frequency is 10K.

    For 5V output, it is DC to drive the relay.

    So will this be a problem? thanks.

    Jun Shen

  • In reply to Jason Shen:

    Sorry, below is the right one.
    For 5V output to drive the proportional electromagnetic, frequency is 20K.

    For 12V output, it is DC to drive the relay.
  • In reply to Jason Shen:

    Hi Jason,

    Please see the post: e2e.ti.com/.../988064

    Connecting to different PVDD voltages is not recommended.

    In there would be a concern if the CBC current limit activated when using different frequencies on OUT_A and OUT_B. Please refer to section 7.4 of the datasheet for details on how to recover from a CBC activation.

    What are the current requirements? We should be able to suggest an alternative.

    Rick Duncan
    Motor Applications Team

  • In reply to Rick Duncan:

    Hi Jason,

    I am closing this thread, but have contacted you for more information.

    Rick Duncan
    Motor Applications Team

  • In reply to Rick Duncan:

    Hi Duncan

    Thanks for the feedback, and one more confuse for the PVDD_A leakage. when only apply the GVDD_X and VDD with 12V, the PVDD do not have power supply

    we have find a leakage on PVDD from other supply. the PVDD have a 5.4V leakage voltage and using 1k resistor can only pull this pin to 1.2V. so could you kindly suggest where is the leakage from GVDD_X and VDD to PVDD? thanks for your support.

    B.R.

    Jun Shen

  • In reply to Jason Shen:

    Hi Jason,

    I have tried to duplicate the finding using the DRV8412EVM. I was not successful. PVDD only had less than 10 millivolts after 10minutes.

    I can see a small sneak path of ~10nA that could charge the PVDD capacitor.

    Can you send a schematic of how the DRV8412 was connected?

    Rick Duncan
    Motor Applications Team

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