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DRV421: Maximum sensing ratings

Abhi Patni
Prodigy 10 points
Part Number: DRV421

Tool/software:

Hello, a separate E2E thread for this IC confirms this works for 400A current sensing:
DRV421: DRV421 for 400A DC current - Sensors forum - Sensors - TI E2E support forums

However, this may not be the actual maximum sensing range of this IC. Assuming proper compensation, does that number/figure exist? Is there some spec'd linearity or accuracy up to, for example, 1kA? And theoretically it will not saturate/be damaged above some proximal current of, for instance, 5kA at 0.01m distance (beyond which the IC will be destroyed).

So I am looking for clarity on 2 things:

  1. The actual maximum possible current sensing range for this IC, to which its accuracy/linearity specs hold true.
  2. The proximal current beyond which this IC would be permanently damaged, if that value exists. Probably this is a curve correlating distance and field strength.

Thanks very much for the help.

  • 0
    TI__Expert 5310 points

    Abhi,

    Thanks for the question and using the E2E forum.

    We are out of the office due to the U.S. holiday but will respond to your question when we return to the office Monday, 4/21.

  • 0 in reply to Louis L
    TI__Genius 17060 points

    Hello Abhi, 

    Thank you for your patience and your post. 

    Measuring currents up to 1kA with our current set of current sensing products is difficult.

    The difficulty with the DRV421 is the need to increase the drive strength of the compensation pin outputs via an external drive stage. 

    You also have to keep the inductance of your compensation coil in mind as well. 

    To address your first question, I would suggest filling out this DRV421 System Parameter Calculator: SLOC329 Calculation tool | TI.com

    This will give you an idea of whether your application is feasible and manufacturable. 

    I do not believe we have a maximum proximal current rating but I would say for the measurement current to keep the magnetic field in the core below 1.7mT as per the saturation level in the datasheet. 

    I hope this helps, 

    Joe