Inrush current for Pololu 172:1 Metal Gearmotor 25Dx56L mm HP 6V

Hi, I have task to deal with:
I have Pololu 172:1 Metal Gearmotor 25Dx56L mm HP 6V and I have problem. It will move repeatedly, with some weight attached, back and forth fast for about 45-90 degrees so all the times it will start, stop and start in different direction.
It is written that at 6 V current is 550 mA (max) free-run and 6.5 A stall.
I need to know inrush current for this motor.
I have power supply with out 12V 5A so I planned on using step-down transformers connected in parallel to have 6V and (theoretically) 10A. Then i found out that stale current and inrush current are not the same.
Can anyone tell me what’s exact inrush current?
I can go down to 5V to have >12A or buy power supply with 12V 10A output so with step-downs I would get like 20A (practically less than 18). Second solution is very expensive to me but if there is no other…
Please, help me, this task is very important and now I’m scared.
(sorry if my english hurts your eyes, it is not my native).


It is common for DC motors like these to briefly draw spikes of current up to their stall current when driven at 100% duty cycle from rest. If you are switching between full-speed in one direction to full-speed in the other direction, you could see spikes upwards of twice the stall current. These spikes are very brief, but if you are concerned about them or they are causing problems, you might try implementing some acceleration ramping.

By the way, it sounds like you might be planning on using two voltage regulators with their outputs paralleled; please note that we do not recommend paralleling regulators like that. You can find more details about that in this forum thread. but it is typically better to use a single step-down regulator that can handle the current draw of your application.