Hi
I am trying to add a charge circuit to an arduino ethernet so that it will act as a UPS.
I would like to know where on the board I can get power before it passes through the voltage regulators so that it can be charged if it is using the POE module or the power plug.
Please restate your question, it doesnt make sense. (at least not to me)
Basically I have a charge circuit an lipo battery that I want to connect to an arduino ethernet so it would act as a UPS for it.
However i want to connect it in a way that if it being powered by the POE module or the power plug it will still be able to charge the battery and supply power when the mains go off.
Ok I figured out that all the +ve pins for voltage input on the arduino are all connected.
Now all I need is a way to switch to the battery when my 9V power supply cuts. The battery will have a voltage of 7.4V, would I be able to use a transistor to select the highest voltage coming in from the 2 supplies?
You could have a simple relay that's powered off the mains switch it to battery, then when I goes off the battery is automatically connected, so long as you have a decent capacitor it shouldn't mind the momemtary loss
mrjonny2:
Ok I figured out that all the +ve pins for voltage input on the arduino are all connected.
Now all I need is a way to switch to the battery when my 9V power supply cuts. The battery will have a voltage of 7.4V, would I be able to use a transistor to select the highest voltage coming in from the 2 supplies?
You just need to common the grounds and then feed each of the +ve connections through a diode to the Arduino Vin. The supply with the highest voltage will be the one that current is drawn from.
The Arduino already has a diode between the barrel jack and the Vin pin. So you can connect one of the supplies directly to the barrel jack and the other through a diode (1N4001 or similar) to Vin.