Need to design a circuit that uses Arduino to control a 5-48V DC motor. Is the circuit shown feasible?
Sorry, that circuit is complete nonsense. Try again.
(The motor should be between the drain of the FET and the supply, and there should be a reverse protection diode across it. What do you imagine the Zener and Schottky diodes and Q1 do?)
The motor should be between the drain of the FET and the supply, and there should be a reverse protection diode across it.
My thoughts exactly. I don't see how that fet could control the motor. It's not in the same current loop as the motor so all it can do is divert current , which accomplishes nothing because it doesn't affect motor current.
What do you imagine the Zener and Schottky diodes and Q1 do?
A bit presumptuous of you to assume he knows what a Schottky diode is based on the fact he posted that
schematic , don't you think ?
@OP,
Here's a couple of examples of how it's done (high side switching with a P-channel mosfet and low-side switching with an N-channel mosfet so if you only have one or the other you can still make it work.
Driving motor with mosfet
FYI, the mosfets have to be rated for the full motor current.
I like this animation...
Have you tried driving it with a PWM pin ?
raschemmel:
Have you tried driving it with a PWM pin ?
Is there a problem?Please forgive me, I am a beginner in circuit design. I hope to use PWM to drive. I have tried many circuits and failed because I need to drive high voltage and current.So far there is no one suitable for 5~48V circuit.
Have you built that circuit yet ?
kmimax:
Thanks for everybody, I am sorry, the circuit is wrong, now change....
raschemmel:
Have built that circuit yet ?
Subtle comment that. 
Clearly that circuit is but a modest improvement. 
May I ask from where you are getting these apparently random circuits? 
Correction:
"Have you built that circuit yet ?"
(I'm not going to tell him all he needs is the
mosfet and flyback diode.
I'll let someone else do that...
and ?
raschemmel:
Correction:"Have you built that circuit yet ?"
(I'm not going to tell him all he needs is the
mosfet and flyback diode.I'll let someone else do that...
I was also wondering why not use only the mosfet and diode and maybe a resistor from gate to ground just to be on the safe side. Specially if you use a logic gate mosfet like the IRL540 yes ?
kmimax:
Tried such a circuit
And that circuit looks correct, except that it will only function (reliably) with a minimum supply voltage of 15 V.
If you want it to operate on less than that, you do need different components.
Paul__B:
And that circuit looks correct, except that it will only function (reliably) with a minimum supply voltage of 15 V.If you want it to operate on less than that, you do need different components.
If it is 5~48V, just choose a high voltage MOSFET?
It's not the voltage rating of the MOSFET, it is the fact that that particular one requires more than 10 V to turn on, and when you apply 5 V to the base of the 2N3904, it pulls the gate down to 5 V. 10 + 5 is 15 V, so the FET will not turn on with a lower supply voltage.
If you also want the motor to be reversible, search for H-Bridge motor control circuits.
kmimax:
How will you correct the circuit?
I will try to lay out a diagram for you. I just dont have the time to do so right low. Ill probably do it tomorrow.
Hi,
Is there a reason you are using HIGH SIDE switching?
If not.
LOW SIDE switching uses less components and is less complicated.
Can you tell us your electronics, programming, arduino, hardware experience?
Tom.... 
This is what i can think of. I dont know if it will work for you.
Note that the IRL540 can handle up to 100V drain to source and up to 20A maximum
If the motor requires less than 20A then you should be ok whthout relay but with a heatsink.
If your supply voltage is not steady then you will probably not be able to use the relay version.
P.S.
in suggestion 2 i mention "if motor needs more than 18A"...
The correct is "if motor needs NO more than 18A".
