High side N mosfet

Using Arduino Motors, Mechanics, Power and CNC
1

I need to high-side drive a dc motor. I am missing a P channel mosfet, so till I get one I want to test my thing with an N channel one. I plan to drive it with an isolated battery and an optocoupler. Here is the schematic

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Should it work, or is my schematic bad? Maybe someone can give me some tips, or a better way of doing this. Thanks!

2

Thanks for the schematics!
For a first test I suggest You use the N channel FET switching the low side. I'm a bit rusty and don't want to "guarantee" the correctness of Your circuit.
The position of R1 looks a little bit odd to me. I would like it placed between the ´gate and the source to make sure the off gate voltage goes low.

3

Oops, my bad! Little error with the resistor. Fixed it now.

4

No battery needed. A capacitor will do.

There are "bootstrap" chips to drive N-channel MOSFETS on the high side, or you can make your own.

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5

Thanks for stepping in.

6

What is your reason for not using the MOSFET on the low side ?

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