Current to motor driver?

Hi all,

I found this nice motor driver that I was planning on using on some 12V DC motors with 3.6A stall current. So I understand that I won't need a full 3.6A to each motor, and I actually connected a power source and found that even 12VDC and .20-.26 A was enough to run the motor as fast as I need. What I'm wondering is, what current I would actually need to supply as motor power? Can I just say .263 + safety factor? The driver apparently can take up to 4A per channel, but I'm assuming I can't go ahead and provide 43A, because that would be crazy and probably kill me?

you can drive a motor to make it spin fast with very little current
when you place it in your project it may draw way more for having torque as well

How can I figure out the power supply current I'd need to provide to the motors then? Since there are three of them and the power supply goes into the one chip. Maybe I can use the Adafruit driver after all. Think I can just call it good at 1.5A?


you should measure the current consumption of a singe motor under load. The load on the motor is causing the current, the voltage causes the rpm while free spinning. If there is not much load on the motors during normal operation you should be fine with a 1.5A to 2A 12V DC supply. With the motor driver you are using (the 4 channel one) you could even read out the motor current of each motor and eventually shut it down when they are stalled or the load gets to big.

Regarding your other questions from your other post ("Motor shield to control 3 12V DC motors?"), I try to answer them in that post.

but I'm assuming I can't go ahead and provide 4*3A, because that would be crazy and probably kill me?

FYI, you don't decide how much current is supplied. You decide how much current you CAN supply. How much current supplied by the power supply (and therefore the motor driver) is decided by how much the load draws. You can choose motors that draw more or less and you can power it with a power supply that supplies more or less but that is the extent to which you influence how much current is supplied.