Can anyone tell me if there is any potential issue with switching the DC power on and off with a drv8825 or a4988? Is it possible this can ruin the driver board. My application is a simple microcontroller (atmega 168) controlling a single stepper driven by either an a4988 or a drv8825. The circuit is powered via a 12V ac to dc wallwart. I’d like to have a simple mechanical power switch to turn on and off the circuit. Is there an issue doing this? Is there any concern if the dc was switched off while the motor is turning?
The setup you mentioned should be fine, as long as you are powering down the whole system (i.e., not just the motor) at once. We recommend putting a capacitor across VMOT and GND to minimize the effects of LC spikes when you apply power.