DRV8825 motor driver - motor winding pins polarity

[newtekuser]

Very noob question:

Per the data sheet of this IC, positive current for the motor winding pins goes from AOUT1 -> AOUT2 and BOUT1 to BOUT2.
Does this mean BOUT1/AOUT1 are positive and BOUT2/AOUT1 are negative, or is it backwards? I know electron flow is from negative to positive, but convention is backwards. However, I do not want to blow up my motor 

If this goes by convention rather than actual electron flow, then it should be A1 is +, A2 is - and similar for channel B, correct?

[DavidAlfa]

You can't blow a DC motor with the wrong polarity, it will just run backwards.

[newtekuser]

You can't blow a DC motor with the wrong polarity, it will just run backwards.

That’s what I thought too, but got confused when some folks left negative reviews on amazon that wires were labeled incorrectly and blew their motors.

[aliarifat794]

AOUT1 and BOUT1 are typically connected to the positive terminal of the motor windings.
AOUT2 and BOUT2 are typically connected to the negative terminal of the motor windings.
Here is also the datasheet of DRV8825:
https://www.ti.com/lit/ds/symlink/drv8825.pdf

[pcprogrammer]

The DRV8825 is a somewhat dedicated stepper motor driver, and normally is connected to a single stepper motor that has two windings. The stepper motor has to be properly connected to be turning.

The outputs are not labeled + or - because they can be either. Internally there is a H-bridge per winding, that can connect one output to the + and the other to the -, or the other way round, or have them both floating, or short a winding to apply break.

Based on the DIR input the stepper motor will move in either forward or backward direction when step is pulsed.

So it is not so much that the outputs need to be polarity correct but more phase correct. Look into how a stepper motor works to see what I mean with that.

For driving a normal DC motor there are better motor drivers out there. Either with a single H-bridge for one motor or multiple bridges to drive more motors.