Single power source multiple devices

This is something I have never been sure about. Powering the arduino and other things from the same power supply. In the attached example is this possible?

I am building a display for an event, but the servo requires external power. I also intend on having some LED strip lighting hooked up. I have it all working on my bench with the servo running off its own battery source, but for the completed project I would like to have only one power supply for the entire thing. I intend on using either a 12v plug in (2amp) or a 12v battery.

Question is: Can I just tap off the main power supply like shown (like double plugging).
What do I need to step the power down for the servo so as to not fry that?
Do the amps pulled by the LED strip interfere with the power into the arduino.

Sorry if these seems like an stupid question, but I really have no idea.

Appreciate any advice.

you’d be better off using a voltage regulator, e.g. set this one for 9V one for the Arduino

and powering the Stepper from a stepper shield:

although that may be overkill and you’ll find cheaper equivalents elsewhere on line.

Also, if you want to control the LEDs look at:

As for your question about the LED affecting the Arduino, 2 amps from a battery will run it down quickly, e.g. a 7AH battery is ‘7 Amps for 1 Hour’ to supply 2 Amps you would get 3.5 Hours, possibly less.


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Thanks Dave.
I do have the Servo shield but don’t want to use it. I found it painful to use as I cannot then access all my other pins which I need for the various other things the arduino is doing. Also, it is overkill for one servo. On my bench it is running brilliantly without the need for the shield.
I will actually be using a 12v power supply for the project, not a battery, I had worked out it wasn’t going to last long with the LED strip after I posted my question. I don’t need to control the LEDS, it is part of a neon strip which only highlights the display. Nothing fancy.

My aim is to to have it working like my circuit shows, but with one power supply for the lot. The regulator is what it looks like I need between the power supply and the servo. I’ll have to try and order one.

Thanks heaps!