Solenoid - 14.4 volts / 11 amps

Hello everyone, i just started using arduino and new to electrical engineering too. Probably this question was asked before, but i can't find to get my head around it.

I need to control a solenoid which feeds onto 14.4 volts, from my car battery, and can have a max current draw of 11 Amps.

I want to use arduino pvm to control it's speed and control the nos flowing trough it.

I have found the circuit bellow using a TIP102 transistor but obviously that is not powerful enough for my application. Any ideas of a "bigger brother transistor i could use in the circuit bellow" or some similar circuit please?

Circuit Diagram

Kind Regards

The current thru the solenoid coil can be 11Amps? Wow!

Going to need a pretty hefty duty MOSFET - go with an N-channel between the solenoid ‘-’ and Gnd.
Part like this
With .005 ohm on resistance, will dissipate 605mW with 11A, so will not need much heatsinking.
Be sure to have a high current rated diode across the solenoid coil to dissipate coil-generated current when the transistor turns off. (collapsing magnetic field in the coil tries to keep current flowing, diode gives it a path to dissipate in the coil).

Drive the MOSFET with a MOSFET driver chip if you are going to PWM it (which it sounds as if you are). A 20A+ rated schottky diode in TO220 format bolted to a heatsink might be a wise choice for the freewheel diode. You would be wise to opto-isolate the signal into the MOSFET driver too for good measure.

Thank you CrossRoads. it is exactly what I was looking for and that mosfet will make as a good first trial run.

can i get the ICL7667 driver for use with the mosfet and arduino ?

thank you.

can i get the ICL7667 driver for use with the mosfet and arduino ?

Looks like you can.

I don't know how you think you can control the "speed" of a solenoid.

The normal type of solenoid is designed to have the moving part in one position when energised, and the other position when de-energised.

The speed of it's movement is going to be dictated more by its own inertia and any springs present, than anything you can do with the coil current.

It's a gas valve, probably held closed by a spring when the power is off. Variable power allows controlling the orifice in the valve and hence the gas flow. The speed of the gas is what needs to be controlled.

guys thanks a lot. the ICL7667 and TO-251 in the scheme above works great. using the circuit now i highly doubt there is a 11A max current draw, but that's what the papers say.

Anyway thinking to step it up a notch and instead of controlling the purge valve, start controlling the fuel and nos solenoids (i want progressive feed starting from 25% to 100% so I can run more power without shocking the engine). they are the same as purge valve solenoid, but encased in 1 piece, wired in parallel. Meaning this time I need something for 22Amp max current draw at 14.4 volts.

Is there some even bigger MOSFET? or I was thinking to use this motor drive instead (15A without heatsink). I believe it should be the same, disregarding the fact it says is for motors? :cold_sweat: (sorry for stupid question)

Kind Regards,

If it's a gas valve that is designed to modulate and has a maximum current of 11amps, are you certain it isn't an AC driven valve.

is DC only for sure. i guess it has to have a set power and due to that it has to high amp usage due to low voltage available in the car.

Hi, Do you know if this solenoid valve will work using PWM, you have to have the right PWM frequency and a specific valve seat taper for PWM to work. If you valve is designed for a simple OPEN/CLOSE operation, it is highly unlikely that it will perform in a proportional flow situation.

Tom.... :)

Hello TOM,

Yes they will work with PWM but there is no data regarding the frequency and rest. This is I think because NXExpress themselves sell the "progressive controllers" as a separate piece of kit which is about $399. They are also rated at 45Amps, but 22AMPS will do in my case as the solenoids are smaller. I could still use same circuit as per first attempt if I can find a powerfull enough mosfet to switch it.

The link for NXExpress progressive controller:

Function I need is just set duty cycle start at 25% for example and ramp of 25% every 0.5 seconds, something like that. no other features.