Arduino supply in 5v pin

Hi,
I need some information. I have solar panel 5.5 V, 3,7 Li-ion battery, DC-DC Converter Step Up Module 0.9-5V to 5V, Li-ion Charger Board 18650 Lithium Battery and some sensors.

I want to use the battery to supply my arduino uno. A friend told me to connect the boost converter output to Arduino 5V pin instead of Vin. Can i do that and what i gain if i do it?

Thanks for response in advance :slight_smile:

Yes you can do that.
In addition, connect a 1N4001 type diode from the regulator 5V output (anode) to its input (Vin, cathode) so the regulator is not reverse driven too much, thus not potentially damaging the regulator if you decide to use it later.
What do you gain? More efficient regulation - no need to run a higher voltage thru the linear regulator to make 5V.

To get 5v from the regulator, you need like 7 on Vin, and 2/7ths of your power input will be wasted as heat.

Thanks for the advice :slight_smile: