What is the AREF pin on the Arduino UNO used for?

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Multiple Choice

What is the AREF pin on the Arduino UNO used for?

The AREF pin is the Analog Reference input. It defines the voltage against which the ADC compares the inputs when converting analog signals to digital values. The Arduino Uno’s ADC is 10-bit, so its readings range from 0 to 1023 for 0 up to the chosen reference voltage. By default, the reference is the board’s supply (Vcc), so 0–5V maps to 0–1023. You can provide a different external reference to AREF to improve precision for signals that stay within a smaller range; in that case you use the external reference setting in code (analogReference(EXTERNAL)) and typically add a decoupling capacitor between AREF and ground. Just be careful not to exceed the reference voltage or Vcc on AREF. This pin isn’t used for interrupts, reset, or PWM.

The AREF pin is the Analog Reference input. It defines the voltage against which the ADC compares the inputs when converting analog signals to digital values. The Arduino Uno’s ADC is 10-bit, so its readings range from 0 to 1023 for 0 up to the chosen reference voltage. By default, the reference is the board’s supply (Vcc), so 0–5V maps to 0–1023. You can provide a different external reference to AREF to improve precision for signals that stay within a smaller range; in that case you use the external reference setting in code (analogReference(EXTERNAL)) and typically add a decoupling capacitor between AREF and ground. Just be careful not to exceed the reference voltage or Vcc on AREF. This pin isn’t used for interrupts, reset, or PWM.

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