Chan's Kingdom

Arduino Uninterruptible Power Supply (UPS)

Recently a friend of mine asked me to design a simple Uninterruptible Power Supply for Arduino using some handphone battery ( Li-ion) and handphone charger.

I decided to use a TP4056 charger board to charge the battery, while using a P-MOSFET to control when will the battery provide power to a 5V Step Up Converter.



The schematic shows the 5V from a handphone USB charger feeding a 5V Boost Converter, which powers an Arduino Uno. The 5V will also charge the Li-Ion via TP4056 board. If the USB Supply is gone, the P-MOSFET will be switched on and the Li-Ion battery can power the Boost Converter.

( on second thought, now I am thinking about the usefulness of the P-MOS. I was thinking of switching the battery on and off but now I think it serves no purpose... LOL)

Anyway, the 2 diodes are 1N5158 , I forgot to change it on the schematic. I think the P-MOS can be eliminated because the 5V from the USB would have prevented the battery from supplying power anyway.



This is my end result on a perf board. My friend says that it is working fine, at least until now. (I have no confidence in my design).

Cheers!

p/s :for the improved design, go to http://chanskingdom.blogspot.my/2016/10/arduino-uninterruptible-power-supply.html

Labels: Arduino