To make efficient use of battery, step-up or step-down converter is needed (depends of battery configuration). Good one have efficiency above 90%, 80% is a bad one :-)Don't use on-board LDO for this. Most such regulators have 'shutdown' pin. You can get regulator with very low shutdown current (microamps) and implement soft shutdown.This is my quite old project powered from li-ion batteries with this feature:On the top-left part of schematic you have power section.There are 2 components:- voltage measuring circuit (D1, R7)- shutdown circuit (D2, R9, C7, D3)How it works:Start:- you press power switch- C7 is already discharged, so it sets shutdown pin of converter to high- converter is enabled and passes power to the rest of circuit- cpu starts- first thing cpu does is putting PB2 high- PB2 is connected via diode D2 to shutdown input and it sets high voltage there before C7 is dischargedStop:- cpu use ADC to get battery voltage- if voltage is too low, it finishes all operations and sets PB2 to low- C7 discharges through R9- when C7 is discharged, converter stops- whole circuit draws only converter standby currentOf course it's only one option. If you don't trust your code, it's better to use just battery protection circuit. But soft shutdown is good choice when you need clean shutdown (for example to finish write to sd card etc.).
Hey, So you reckon powering the mini with 4.8V is better than using a 7.4V?
most efficient solution is running an m328 directly off 1s lipo.
Would I be able to use the SparkFun LiPo Fuel Gauge and program the Arduino to enter sleep mode at 3V?If I disable the power LED and since I am bypassing the Linear regulator the current consumption will be 0.0058 mA is that good enough?
Except if you have bunch of 5V powered peripherials as in that case...
Except if you have bunch of 5V powered peripherials as in that case...What about other parts? Could you put them into sleep mode as well?If you need to protect battery, you need to really shut down everything, to single microamps.About battery protection - check step-up converters as some of them already have such protection.
Wouldnt all the peripherals cease working if the Arduino is put in sleep mode?