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Questions relating to designing PCBs
By xpcker
#189748
Hi guys,

i`ve been smashing my head to the keyboard for the past 2 days trying to figure this out, hope anyone can help me ^^

- i want to make a circuit so i can connect it to three things,
- 12V DC Power supply
- SLA battery 7AH
- Arduino or 5V component.

-------> Arduino/12V/5V
Power supply ------> (circuit i want to make) ------> battery


So the idea is to power this circuit to 12v, so it can charges the SLA battery and use the arduino at the same time, when the current cuts off i need the battery to kick in. Hopefully i dont want to use the same arduino as the current controller, i saw maximm and diodes chips but cant find one that suit this.

What are my problems or doubts?

- i know i can use a LDO to charge the bat but i need to have it always connected and it doesnt have the logic.
- can i keep the battery always charging? (i think not probably it will swell and explode or die)
. is it ok to have a charger for the battery and plug my arduino directly to battery? like in series? (of course with a 12v to 5v dc-dc converter in the middle)

thanks!

Juan