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DRV8305-Q1: High side gate driver Vgs voltage

Genius 14680 points
Part Number: DRV8305-Q1
Other Parts Discussed in Thread: TEST

Hi all

My customer is using the DRV8305-Q1 and has below question.

Please review and comment.

Best regards

Ueli

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I’m looking to update my mosfet and I was wondering how the charge pump + high side power supply react in low PVDD voltage and Igate higher than 6mA.

Do you have some data showing this case ? especially the min Vghs ?

In my worst case I get Igate = 13.6mA (170nC) @ Vgs = 10V / 20kHz PWM / and for 4 Mosfet switch per PWM period (BLDC application)

  • Hi Ueli,

    We need to look into our database to see if this information exists. May you explain how you were able to test for Igate = 13.6mA so we can replicate the test setup on our side here if we need to on the bench?

    Thanks,
    Aaron

  • Hi Aaron

    Thank you for the quick reply, I will check this with the customer.

    Best regards

    Ueli

  • Hi Ueli,

    Thanks! 

    Best Regards,
    Andrew

  • Hi Ueli,

    Aligned internally with the systems team, and we have a response for you on this - thanks for your patience.

    Please see the info below, and let me know if it resolves your question. 

    • In the customer's request, they are asking for the device performance in a condition that is not guaranteed by the datasheet spec.
    • We are not able to provide an estimated value for VGHS voltage that would be true across temperature conditions and manufacturing process variation, so this may be something that the customer has to validate themselves if they are intending to use it that way

    From a system perspective, the customer's usage condition could possibly pull too much current from the VCPH regulator and cause VGHS voltage to dip lower, of course, which is expected. 

    • One thing the customer can do to help prevent this is to: reduce PWM frequency to lower the load on the VGHS voltage 

    Thanks and Best Regards,
    Andrew

  • Hi Andrew

    Thank you for the clarification and no problem, I appreciate your support.

    Best regards

    Ueli