I have one project, where I'm going to use two stepper motors and two EasyDrivers. The power supply to the motors, through the EasyDrivers, will be 24 V. The controlling bord will be an Arduino Uno.
It would be nice if I just could use the 24 V power supply for everything. The EasyDriver has a 5 V output, max 70 mA according to this page. Am I safe if I connect the 24 V to both EasyDriver boards, then I connect both of the 5 V output to my Arduino Uno? The Uno is said to use 50 mA while idling. But the supply would be 140 mA, so it should be enough, right? The Uno will drive the two stepper motors through the two EasyDrivers, probably one solenoid, too, through its own transistor.
What makes me thinking is that the 5 V output of the EasyDriver is said to be for "external circuitry". Since the max output is 70 mA and the Uno runs at around 50 mA when idle, does "external circuitry" only mean like simple sensors and not control boards like Arduino?
The 24 V suppy is from the power unit from an old typewriter (220 V AC -> 24 V DC).