How Can I Control an Electromagnet with a MOSFET for a 9V, 6A Project?

[Daniel0811]

I'm working on a project where i need to control an electromagnet but I'm not sure how to do it. I tried using a npn but the current passing through the magnet is just to small, should I use a mosfet instead.
The specifications for my project say that they will provide us with 9 volts and a maximum of 6 amperes, but how do i reduce that current (because it's too much right?) and how should I connect my circuit?
Any help will be appreciated
Thanks

 

[davenn]

I'm working on a project where i need to control an electromagnet but I'm not sure how to do it.

Hi Daniel
welcome to PF

what do you mean by "control an electromagnet" ?
in what way do you want to control it ?Dave

 

[Daniel0811]

I need to control it with an atmega 328. I don't care too much about the software part because as far as I know I just need to enable one of the pins of the chip to activate the transistor, the thing is that I'm not sure which transistor I should use. I was using a voltage supply with 9 volts and about 1 amp but when I used the transistor the current dropped to 0.3 amp. I don't know if I'm doing something wrong or maybe I'm not using an appropriate transistor

 

[meBigGuy]

Not enough drive. You need enough drive to cause the transistor to saturate, generally about 100ma to saturate 1A. Obviously the atmega can't do that.

You can go to a darlington, or a smart power fet such as I linked at the end of this post
https://www.physicsforums.com/threads/electromagnet-and-mosfets.831892/#post-5224970

Don't forget the flyback diode.