Hey Guys!
First of all sorry for any stupid questions, I am primarily a SW engineer, I do electronics as a hobby
I am planning to run my project on Liion cells. As i know moteduino has a low dropout linear regulator which is great, because it still outputs 3.3V with 3.3V battery voltage. However these Liion cells can discharge down to 2.9V without damaging the battery.
The question is, will the LDO output 3.0 volts if the battery can only supply 3.0? Both Atm328p and RFM69HW can work at that voltage.
Given the fact, that i am going to use 2 liion cells for a moteduino based node. Which configuration would be more energy and performance efficient:
- 2 cells in series
- 2 cells in parallel
If my knowledge of linear regulators are right, supplying any voltage higher than 3.3V will be burned to heat right?
So this way 2 cells in parallel would be more energy efficient even I can't use the batteries whole voltage range (2.9-4.1 vs 3.3-4.1)
Random fact for those interested:
I am creating an urban garage alarm with moteduinos. The difficulty is that it's an open garage on the -1 floor in a 10 story building. I need to create a reliable connection between -1 and 4th floor. There is a lot of electronics stuff, wifi, concrete and metal and like 100m horizontal distance between the transmitter and the receiver. So I might need to use a repeater node. However the transmitter and the relay needs to be run on battery power. The transmitter is not a big deal, because it can sleep a lot.
However the repeater can't sleep much, because it would lose signal from the transmitter while it is sleeping. I might end up running the repeater on like 20 liion cells wired in parallels (around ~30000mah i got a quite lot of them from used laptop batteries).