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I am building a PCB that consists of a stepper motor driver (DRV8711) and had a confusion with the N-Channel MOSFET selection. I will power the driver through a 50V supply and the driver mentions typical gate drive voltage to be +10V higher than the supplied voltage. Which is the confusing part because I have never seen a MOSFET with max Vgs higher than it's max Vds. Is it constructed so that the short charging pulses don't damage the MOSFET?

In the official boost evaluation board TI also used a MOSFET with 20V Max Vgs while stating the board can be used with 24V which equals to around 34V gate voltage.

Absolute maximum ratings

Absolute maximum ratings

Typical MOSFET gate drive voltage

Typical MOSFET gate drive voltage

Source of above images: Texas Instruments - DRV8711 datasheet

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    \$\begingroup\$ Gate voltage, not gate-source voltage. It's measured to GND, not source :) \$\endgroup\$
    – Tim Williams
    Commented Sep 17, 2023 at 18:58
  • \$\begingroup\$ @TimWilliams Thanks. It helped me in addition to the answer. \$\endgroup\$
    – Berkays
    Commented Sep 17, 2023 at 21:57

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Note that the VM+10 spec only applies to the high side FET. When the high side is on, the drain and source will be very close to the supply voltage, so the gate to source voltage will be roughly 10 V. So your FET need only be spec'd for a maximum Vgs of 10 V plus whatever margin you feel is necessary.

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