Best way to drive an electromagnet that needs to alternate to pump air.

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Joined Dec 29, 2020

I have an aquarium pump that is no longer being used and I want to integrate it into a design of mine.

The pump plugs into mains voltage and seems to have a potentiometer and some passives to control the amplitude, and what i believe is a flyback diode for the inductive load.

I am inexperienced designing for stuff with high voltage AC; but i've done many <12volt DC electronics designs.

At first I was thinking of pluggined mains power directly into my PCB using something like an IEC320 connector and then using a PCB mounted AC-DC power supply to step down to 5 volts for the rest of my design (raspberry pi zero, stepper motors, LCD display, etc) and have the AC side of the PCB feed into a relay that connects to the pump and have the relay switched with the raspberry pi's logic level output. This seemed like an okay approach but it also has me nervous since i've never used high voltage and in addition the PCB mount switching power supply i'd need to go from 120VAC to 5VDC (I need 10A on the 5 volt side) would be huge and unwieldy to design around. [That part alone would take up half of my planned PCB board space](

I was wondering if a better idea was to use a commercially available power brick to provide 12VDC 10-15A to the board and then make a smaller section of the PCB somehow drive the AC electromagnet. Is this called an inverter? Is it simple to design one or should equal caution be used when making one or is this better to buy? I only found a couple on digikey and they were fairly expensive.

Here are some photos of the pump:

EDIT: Would an
I only plan to use "half" of it since it's essentially to electromagnets each of them pushing two diaphragms. So I only intend to use one electromagnet pushing two diaphragms

The [product link]( shows that the entire unit only uses 6 watts at 120VAC, i only need half the unit so the section I would need would use 3W@120VAC; quick calculation means one half only uses 25mA of AC current. Does it seem reasonable to be able to convert 12VDC to AC for something this low power?

What do you all think? Should I use the huge PCB mount AC-DC converter with a relay thrown from the 5V side? Or is there another circuit I could build if instead I supplied 12VDC 15A and used a section of PCB to convert to higher voltage AC?

[I've also found these]( but the output frequency is too high to drive the electromagnet correctly.

Would an H-Bridge driver work for this? Is there recommendation for a driver that automatically will switch at a set rate?