Turning on parallel mosfets with an npn controlled by a microcontroller

I have attached an image indicating how to turn on two parallel mosfets using an npn which is turn attached to a microcontroller. However I am unsure if this would actually work. I would normally test this out on a circuit board but I don't currently have any hardware available. Is this right or am I missing something?

Well the NPN shorts 3.3V directly to ground when it is on and I'm sure you don't want that to happen.
There are basically two reasons to parallel MOSFETs, to split the power dissipation or because you can't find a single MOSFET to handle the current you need.
What is your reason?

Mainly to split power dissipation any other reason will be treated as secondary for now.

  • Will your MOSFETs work at Vgs = 3V ?

Yes it will. In fact it has a threshold voltage of 1.2v and +/-20v absolute gate-source voltage

  • We do not look at the threshold voltage to determine this.

  • Please give us the MOSFET part number.

If it does not have a specification for a maximum Rds(on) at a Vgs of 3.3V or less you need to look for another MOSFET

Will this just be ON/OFF or is PWM involved?

Yes, just for turn on/off

here is the datasheet to similar mosfet I intend to use as I seem to have misplaced the actual one

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Similar doesn't cut it at all.

If the FET you used was identical to this data sheet then it would be totally unsuitable for your needs. As the only quoted Rds figures require a 10V gate signal. You only have a 3V3 signal.

The gate threshold voltage only tells you when it starts to turn on in the linear mode. That means it will be generating a great amount of heat.

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What is your load?
What are its specifications?
Please post a link to specs/data of the load.

Thanks.. Tom... :smiley: :+1: :coffee: :australia:

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You need to find another.

This may or may not work

I am glad you added the gate resistors, that will keep it from oscillating.