Arduino Forum

Using Arduino => Microcontrollers => Topic started by: carlosserious on Jan 22, 2020, 08:33 am

Title: ATMEGA328p Power 3.3v boost?
Post by: carlosserious on Jan 22, 2020, 08:33 am
I currently have a circuit I'm working on that runs on a 'barebones' arduino. I want to power it with a 3.3v input, like 3 aa batteries(I know it's 4.5, close enough), as it drains below 2.7v, the circuit will cut off.

Is it worth adding a boost module to get more life out of the batteries and establish a consistent 3.3v operation?
Title: Re: ATMEGA328p Power 3.3v boost?
Post by: srnet on Jan 22, 2020, 09:11 am
If its a bare bones Arduino set the BOD level to 1.8V.

Title: Re: ATMEGA328p Power 3.3v boost?
Post by: ShermanP on Jan 22, 2020, 07:17 pm
I don't think a boost regulator makes sense.  By the time the AAs are down to .9V each, they will be pretty close to being fully discharged.  And if you add a regulator, you will inevitably lose some efficiency - maybe 10-15%.  It's not at all certain that adding the regulator would increase battery life.  It might reduce it.

Title: Re: ATMEGA328p Power 3.3v boost?
Post by: DrAzzy on Jan 22, 2020, 08:30 pm
I don't think a boost regulator makes sense.  By the time the AAs are down to .9V each, they will be pretty close to being fully discharged.  And if you add a regulator, you will inevitably lose some efficiency - maybe 10-15%.  It's not at all certain that adding the regulator would increase battery life.  It might reduce it.


Agree. If you use sleep to reduce power consumption, it definitely will, because the quiescent current of the regulator will continue no matter what (this is even true of a linear regulator, where the quiescent current is much lower than a boost regulator; it's easy to forget just how low the current drawn by a sleeping microcontroller can be).