How to power a microchip off 2 batteries?

[garynorris]

Hi

I have a pic microchip and use 2 batteries. I would like to power the pic off 2 batteries in case one depletes. I tried using a voltage regulator but it it was causing my supplies to short when I connect it to a different board but without this board it works fine. Any other ideas?

Thanks

 

[kam1787]

I am not clear on what you have and want.

Now, you are using 2 batteries in series?

You want to have the batteries in parallel?

What regulator did you use? Can you show the circuit?

 

[FvM]

Gnerally speaking, it's surely possible. You didn't show what you have been trying, so we can't see what's the problem with your design.

 

[garynorris]

I attached a quick overview. So I have 2 batteries and a charger board to charge the batteries. The board receives commands through spi from the microchip which is being powered by a LDO. If I disconnect the charger board I have no issues with the micropic as it gets 16.8V. When I connect to the board the one of the supplies shorts.

Hope that clear

 

[FvM]

When I connect to the board the one of the supplies shorts.

That's true according to the schematic. So no idea how the circuit is intended to work. I would expect e.g. two batteries ORed by diodes...

 

[thannara123]

I think it can made .but you tell correctly the algorithm what you want ?
want you do like relay ?