I'm doing a project where I use arduino uno with nema23 stepper motor and drv8825 ...
Everything is working, but I need to power the arduino via USB or external power supply and also power the motor / driver with another power supply!
After the project is ready, is it not possible to power the arduino and the motor using the same source?
I imagine that I would need some component to limit the current, but I would like to know what is the most economical and simple way to power my system in this case?
I presume the power supply for the stepper motor is 12v or higher. If you use a step-down module to generate a regulated 5v from that power supply you can power the Arduino with 5v connected to its 5v pin.
If that does not help please give us full details about your project.
Something like an LM2596 buck converter module to generate 5V is probably the cheapest solution. These are
rediculously cheap (so buy 5 or 10 at a time!). They have a quality 10-turn cermet preset pot to set the output voltage and I've used many in projects without problems.
Its the voltage that needs limiting by a regulator or converter, the current is set by the load.
I use 4S 1300mAh 95C lipo that has 16.8V when fully loaded.
I do power the 12V 1500rpm caterpillar motors directly with overvoltage, results in 1770rpm free running.
Then I use a LM2592 step down converter with display that powers a Raspberry Pi3A+ with 5V
And another LM2592 without display that powers three 800lm leds with 9V.
Works perfectly, and display of input voltage tells mee when to switch lipos (I do just above 14V): https://www.raspberrypi.org/forums/viewtopic.php?f=37&t=267999&start=50#p1654214