Hello, I'm new to Arduino and would welcome some advice. I've searched the tutorials and the forum, but I have specific question that I can't find the answer to.
I'm using a Uno to control an S3003 servo. I have a switching mode power supply that I wish to use. The output voltage is variable in steps, including 5V and 7V. I'd like to avoid having two separate power supplies.
From what I have read, I think there are two alternatives:
1) Set the power supply to 7V, connect it to the Uno power input jack, power the servo from the 5V pinout (I'm aware of the current limit).
2) Set the power supply to 5V, connect it to both the Uno 5V socket and directly to the servo.
Regarding (1), many people advise against connecting a servo directly to the Uno, although the tutorials suggest this is OK.
As for (2), some people advise against using 5V socket in this way, due to lack of protection. Writing that, it occurs to me that the 5V for the Uno could be connected to the USB port. Is this a good idea?
So I'm confused! Any information to help me decide which way to go will be gratefully received.