Arduino what is aref

So, here is a simple diagram of what I meant. For example, when you use a pot resistor, you connect the 3 pins to ground, 5V on arduino, and finally to analog pin. In my case I am not using the 5V in arduino uno to power the circuit instead i am using an external 9V battery to power my circuit.

And arduino Uno is connected to laptop USB. If not, how does arduino uno know the reference voltage of ADC.

In arduino website its mentioned by default its either 5V or 3. But thats only if you are powering the circuit using the 5V or 3. You do however need to add a wire from the negative terminal of your 9vdc voltage source to a arduino ground pin. That is both the external circuit and the arduino must share a common ground connection, which you don't show in your drawing. Ok, I forgot to put the common ground.

So which reference will arduino uno take by default 1. So basically, when ever you plug something into arduino uno analog pin it reference it as 5V even if you are using USB to power up arduino Uno and you are powering the circuit whose output is connected to arduino by external source greater than 5V. There is 6 analog pins in arduino Uno, right? Last Revision: Searching Description Configures the reference voltage used for analog input i.

This is the only supported option for the Due. Notes and Warnings After changing the analog reference, the first few readings from analogRead may not be accurate.

The two act as a voltage divider, so, for example, 2. Arduino cares about the privacy and personal data of its users. The privacy policy is meant to inform you on how we process your personal data when you use our services. We need to confirm your email address.

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