Arduino (Wavgat) MEGA 2560 AREF pin as power supply?

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1

Hi, Guys!

I'b building a circuit with MEGA 2560 controller onto my car. I use AM2302 temperature & humidity sensor, whic is connected to the controller via I2C bus.

I can see, that there are SCL-SDA pins, there is the AREF port and a GND. I set AREF as default (5V).

May I use this port to give 5V supply to the AM2302 module? Because there are side-by-side SCL-SDA-AREF-GND pins, it will be easier to connect the sensor to the microcontroller.

What do You think? Is this idea good

Thanks: rcph

2

No, you may not draw power from the AREF pin.

Use the 5v pin.

3

Hello, DrAzzy!

Thank You very much Your help.

rcph

4

rcpilot_hun:
Hi, Guys!

I'b building a circuit with MEGA 2560 controller onto my car. I use AM2302 temperature & humidity sensor, whic is connected to the controller via I2C bus.

I can see, that there are SCL-SDA pins, there is the AREF port and a GND. I set AREF as default (5V).

May I use this port to give 5V supply to the AM2302 module? Because there are side-by-side SCL-SDA-AREF-GND pins, it will be easier to connect the sensor to the microcontroller.

What do You think? Is this idea good

Thanks: rcph

Frankly, I ever wondered, why the engineers had placed the Aref pin at that side close to the I2C pins. It just makes no sense. A repeated Vcc pin would have been much more useful at that location.

And, yes, I did it, I have used Aref as a power supply for my sensor, but only because I exactly knew that the sensor is not requiring more than 2mA and I did not need the analog inputs for anything precise. So, yes you may go for it, but only if you exactly know what you're doing.

5

RIN67630:
Frankly, I ever wondered, why the engineers had placed the Aref pin at that side close to the I2C pins. It just makes no sense. A repeated Vcc pin would have been much more useful at that location.

Before the R3 UNO there was only AREF and GND at that location, there were no I2C pins there.

The R3 UNO added SCL and SDA at that location, thus allowing for bases other than ATmega328 to have the I2C pins in a consistent palce.

All makes sense to me.