ESP8266 Community Forum

- Wed Apr 13, 2016 7:26 am #45411 Hello!

You wrote than you power ESP with AAA batteries. Say please how much and what kind of AAAs you use? If you use 2 typical batteries it means that you power your ESP with 3 volts and it works?

In code I see you check low battery at 2.4 volts. Is ESP correctly works on (2.4-3) volts? As I see in specification, it says that we should power our ESPs with (3-3.6) volts...

- Wed Apr 13, 2016 3:36 pm #45440

Is ESP correctly works on (2.4-3) volts? As I see in specification, it says that we should power our ESPs with (3-3.6) volts... f

Tha data sheet really says 3V, but I have experimented with lower voltage and it worked.
I am not sure if 2.4V is save or even the limit but I have tested at this voltage. Probably the radio strength is degrading.

Rainer

Edit:
I have repeated the test.
I have tested with two NiMH batterys with a nominal 1.2V with a sum of (measured with DVM) somewhat below 2.5V. Here it still worked, the mail transmitted however says that the voltage measured from the ESP was 2.55V.
So it seems save for me to use a Limit of 2.6V in the software.
Still I do not know if this is typical and all modules work with this setting, you have to test ist individually as it is off the guaranteed specification.

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- Fri May 06, 2016 7:16 am #46973

I have repeated the test.
I have tested with two NiMH batterys with a nominal 1.2V with a sum of (measured with DVM) somewhat below 2.5V. Here it still worked, the mail transmitted however says that the voltage measured from the ESP was 2.55V.
So it seems save for me to use a Limit of 2.6V in the software.
Still I do not know if this is typical and all modules work with this setting, you have to test ist individually as it is off the guaranteed specification.

Rainer, thank you for you test. I lean to use MAX1724 as DC-DC converter for ESP8266 power source. This component can give me stable 3.3 volts from battery power.