Do I need voltage regulator for 3.3 battery?

Other Hardware General Electronics
1

Hi. Im using my atmega328 running standalone at 8Mhz.

I am not sure if i need to stabilize the voltage at 3v for best stabilized device.

Does anybody know if I need it or I can just connect a 3.3v direcrly?

2

A 3.3V battery will give 3.3V, that's fine.

However if you want accurate measurements using analogRead() you'll have
to think about the issue that the supply voltage will drop somewhat as the
battery discharges.

What kind of battery BTW? Does it have the current capability for your Arduino/setup?

3

Hi. Actually its a variometer that only drive beeps using a buzzer.

And Yes. I'm using a analog read so I assume that I'll need a voltage regulator, right?

Would you recomend one?

4

You don't need a regulator, just a voltage reference to connect to Aref.
For example

Outputs 2.5V as long as Vin is 2.7V.

5

CrossRoads:
You don't need a regulator, just a voltage reference to connect to Aref.
For example
MAX6102EUR+T Analog Devices Inc./Maxim Integrated | Integrated Circuits (ICs) | DigiKey

Him first of all thank you for your help.

Well I have never used the Aref before and to be honest didn't know what this function was for. ..

Well.. Could you please explain more about what you said in..."Outputs 2.5V as long as Vin is 2.7V."?

And could I use the atmega328 running at 8Mhz at 5v?

Thank you very much.

RODRIGO

6

That part will output a rock solid 2.5V as long as its input is greater than 2.7V per its datasheet.
I'm not quite sure what the command needed is to have Aref connect to external pin vs the internal VCC or 1.1V reference.

Atmega with fuses set for 8 MHz operation will run fine with its VCC at 5V.

7

CrossRoads:
That part will output a rock solid 2.5V as long as its input is greater than 2.7V per its datasheet.
I'm not quite sure what the command needed is to have Aref connect to external pin vs the internal VCC or 1.1V reference.

Atmega with fuses set for 8 MHz operation will run fine with its VCC at 5V.

Hi.. Thank you for your answer.

Just a question.. If I'm using a voltage that may have some variation is recomendable to use AREF, right?

What if my Atmega is powered using a regulated voltage. I this case I could ise the DEFAULT reference.

Am I right?

8

Yes & yes.

9

Thank you for teaching me!!

10

Glad to help.