I'm doing a project with Arduino. I have a small Arduino board that every so often takes measurements from a sensor, but it's idle most of the time -- consuming 6mA. I want to use a small battery to power the board. I have seen batteries like the following one:
It's a 3.7V 100mAh battery. The board requires an input voltage in the range 3.7-4.2V. So, I suppose once the battery starts to drain, the voltage will decrease and the logic on the board may stop working correctly.
Is this correct? Or will the battery sustain 3.7V during most of its capacity?
Assuming the voltage will go lower 3.7V relatively quickly, I can imagine two possible solutions:
- To use a battery with a higher voltage and then use some form of voltage regulator.
- To use a battery with more capacity, hoping that the voltage loss will take longer to occur.
Which option is better? Or what are the tradeoffs from an electrical and efficiency point of view?
Is there any other option?
As some of the comments mention, the logic board indeed runs at 3.3V. It accepts a 3.7-4.2V input voltage and it uses a regulator to bring the voltage down to 3.3V. So I suppose a 3.7V battery will be able to power the board at least while it stays in the plateau section of its discharge curve.
With this new information, I guess my original question only makes sense if the board didn't have its own voltage regulator.