I have a 12v/1.5 amp barrel plug power supply on my Arduino Uno. I have two servos that say they are rated for 4.8v to 6v, but no amps are specified. When my circuit is configured as it is in this image, it appears to work fine. (In my test sketch, I'm constantly and simultaneously rotating them from 0 - 180 degrees and then in reverse.)
But I don't understand why it works. I assumed the 5v pin can only supply 5v of total power to the whole configuration. Is it instead supplying a regulated 5v at as needed between both servos from a total pool of 12v (presumably up to 10v at once)? Do I need voltage regulation? Shouldn't I have to know the amps for the servo(s) and use some sort of resistance?
Thanks for any information and advice you can share on learning about the concepts underlying a situation like this.
Update: I ultimately modified my approach based on the feedback received here by wiring a separate 5v/2a power supply to the breadboard for the two servos, and wiring the rest of the circuit appropriately (using a common ground, etc.).