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Following are the doubts on the gate driver section of a forward converter.

  1. Peak drive voltage = 7.4 V (Shouldn't it be higher, say 10 V or so, usually for driving power MOSFETS?)

enter image description here

  1. Peak MOSFET gate sink current = 1.5 A

enter image description here

Vdrv current limit: 100 mA-> Does that mean, it is the Cvdrv capacitor which provides the high momentary current (1.5 A) while charging the gate of NDRV MOSFET?

enter image description here

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Peak Drive volatge = 7.4V ( Shouldn't it be higher, say 10V or so, usually for driving Power MOSFETS?)

Check this out just for clarity: -

enter image description here

The 7.4 volts is enough for many MOSFETs especially logic level devices. Maybe the data sheet mentions the choice of MOSFET. The data sheet does indicate that there is a development board that can be purchased so, follow those links and see what MOSFETs are recommended on it.

Vdrv Current limit: 100mA-> Does that mean, it is the Cvdrv capacitor which provides the high momentary current (1.5A) while charging the gate of NDRV Mosfet?

This is not the current that can drive the gate of the MOSFET - refer to DRIVER or NDRV for that but, the capacitor mentioned does sustain that NDRV current it seems.

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  • \$\begingroup\$ The EVM board uses FDS86242 which seems to have negligible difference in Rds (on) at Vgs= 7V and 10V. Iam still surprised why the manufacturer has gone for 7.4V drive. As @Unimportant commented earlier ( Iam not seeing the comment now!), its the same voltage which would appear at the NDRV pin. \$\endgroup\$
    – Dynamic_equilibrium
    Commented Feb 15, 2022 at 10:43
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    \$\begingroup\$ Yes, the FDS86242 is a very appropriate choice. I do wish Maxim were better at explaining this in their data sheets - they don't help themselves at all these days it seems. Regards the disappeared comment; mine was deleted too - as he was writing his comment I was amending my answer because I realized that NDRV was powered from VDRV (I should have looked at the picture in your question a bit more closely initially). Never mind it's fixed now. \$\endgroup\$
    – Andy aka
    Commented Feb 15, 2022 at 10:47

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