Current taken to motor-driver ic depends only on the motor load and power supply voltage.
It has nothing to do with the power supply maximum output current.
Simple example:
If you take a 40 volt power supply capable of delivering 10 A current,
and connect load resistor 40 ohms , it takes 1 A current from power source. ( I=U/R)
If you connect 3 pieces 40 ohms resistor to supply , current from power supply is 3A.
If you take out 2 pieces resistor out of supply , current is again 1A.
Current changes only when you change supply voltage or resistor value (Load)
You just need to make sure that the current of power supply for the motor controllers is not too small,
overdimensioning current value in this case is not bad.
As you see above you need take care of voltage and load.