user23325: I'm building a test circuit on an Arduino Nano that consists of a simple 220 Ohm resistor and an LED on pin D2 which is routed back to GND (ground).
It's as simple as this:

It's running a very simple program to blink the LED on and off.  It all works while connected to the USB port.  I know the USB port provides 5V. 
Now I want to run it my Nano and circuit from a 9V battery.  The datasheet says that you can run the Nano on 6V -12V by connecting it to pin 30 (VIN).  Of course, I know I'll have to add a line from GND back to the (common) battery ground also.
When I do that, the voltage on the OUTPUT pin (D2) will never be higher than 5V though, right?
I should not expect any change in output voltage even though I'm changing voltage that is powering the Nano, correct?

user37523: It looks like VIN connects to a LM2940, 5 volt regulator, so the voltage on the OUTPUT pin (D2) will never be higher than 5V.


23325: <p>I'm building a test circuit on an Arduino Nano that consists of a simple 220 Ohm resistor and an LED on pin D2 which is routed back to GND (ground).</p>

<p>It's as simple as this:
<a href="https://i.stack.imgur.com/0EA93.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/0EA93.png" alt="Nano circuit"></a></p>

<p>It's running a very simple program to blink the LED on and off.  It all works while connected to the USB port.  I know the USB port provides 5V. </p>

<p>Now I want to run it my Nano and circuit from a 9V battery.  The datasheet says that you can run the Nano on 6V -12V by connecting it to pin 30 (VIN).  Of course, I know I'll have to add a line from GND back to the (common) battery ground also.</p>

<p>When I do that, the voltage on the OUTPUT pin (D2) will never be higher than 5V though, right?<br>
I should not expect any change in output voltage even though I'm changing voltage that is powering the Nano, correct?</p>
 37523: <p>It looks like VIN connects to a LM2940, 5 volt regulator, so the voltage on the OUTPUT pin (D2) will never be higher than 5V.</p>

<p><a href="https://i.stack.imgur.com/muJ5e.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/muJ5e.png" alt="enter image description here"></a></p>
