[VNH5019 DUAL] Control high current motor

Robotics and electronics discussion Electronics
1

Hi!

I have a 12VDC motor I would like to control with an arduino (and a dual VNH5019 controller).
This motor has constant current draw of 14A, but stall current of 40A and inrush of (maybe, I have no way to control this) 150A. It’s a fan taken from a used car. I don’t need to control the direction, only the speed.
Stall current is above the normal operation limit of the polulu driver shield. I don’t even speak about the potential inrush current, which is way above its 60A limit.
My question: do you think that I could use an intermediary MOSFET which will make the high current connection? My setup would be : Arduino >> VNH5019 DUAL >> IRF1405 >> Motor. It would spare me one channel of the controller for another application and help overcome the current limitation. I have some IRF1405 MOSFET (non logic MOSFET, and I can’t find adequate driver here in Africa, that’s why I plan using the VNH5019) with a max current rating of 169A.

Thanks in advance for your opinion,
Regards,
Tsiresy

2

Hi, Tsiresy.

It is not good practice to use the outputs of a driver as inputs to MOSFETs like that, but it is possible. You might consider our Dual G2 High-Power Motor Driver 18v22 Shield for Arduino. It has active current limiting that defaults to 60A, so it should be able to handle the inrush current of your motor. Though, it would still probably be a good idea to ramp up the speed of the motor to limit the inrush anyway. You might be able to find it at a distributor near you.

-Claire