Control Electromagnet with Maestro?

Hi All,

I have a little 12V, 0.25A electromagnet that I’d like to control using a microcontroller, probably Raspberry Pi. At first, I was thinking I’d use a MOSFET and a diode as per the instructions on various web pages. Then I remembered that I have a Micro Maestro servo controller and wondered if I could use it instead. Is it safe to assume that the Maestro can cope with back EMF from an electromagnet since the same issue occurs with servos? Are there other reasons why trying to control an electromagnet with a Maestro would be a bad idea?

Thanks, in advance, for any advice.


I am not sure what kind of electromagnet you have, but if all you need is to turn off and on a 12V supply for it, you could designate one of the channels on the Maestro as a digital output and use it to turn off and on a MOSFET. You could also designate a channel as a servo and use something like one of our RC Switches with Small Low-Side MOSFET. The Maestro’s signal line alone will not be able to output enough voltage or current.


If the Raspberry Pi is a requirement (i e, you’re not replacing it with the Maestro,) then no, the Maestro cannot directly drive an inductive load. It sends low-current control signals to servos, that have drivers built-in.
Thus, the cheapest way is probably to use a MOSFET and a diode, just like you’ll see on web sites.