There you go.
I was hasty and thought we were talking about a 5 volt battery and a 12.47 volt battery. Now that would make for some excitement.
a7
So if it's OK to connect the two grounds just during measurement the you can use a tiny DPDT or DPST relay. A low current signal relay will do since you basically will not be drawing any current.
OK, so now to my original question.
Can this be done with a transistor instead of a relay?
What current?
Since I built my own I might be able to help but only if you ask questions instead of giving what you think it should be.
Where?
I asked the question in the first post
Ok, since you refuse to listen I will mute you. Bye.
Can this be done with a transistor instead of a relay?
If the grounds can be permanently connected then only the Arduino ADC inputs need to be disconnected from the battery when the Arduino is powered off.
It can be done with two mosfets
Please read again from the beginning. I think you will find that you are the one who is not listening.
You mean you have 3 batteries, right?
- 5 V for the Arduino etc
- Auxiliary 12 V
- Main battery 12 V
No. Two 12.6v batteries and a 5v voltage regulator connected to the main battery
And it's the Aux or Main you wanna monitor?
E: or both?
However it would be much simpler with a relay
It's only 0.6" by 0.3"
Through the transistor.
Anyway, I agree with jim-p, go with relay.
Thank you everyone who tried to help.
To sum things up, I understand that none knows how to solve this challenge with a transistor, and so I will revert to plan B and use a relay.
For those of you who's been asking questions, they are all welcome and I'm doing my best to answer them in the best way possible, but please make sure you've read the whole thread before asking.
I do but you never responded
I thought I answered all your questions. Sorry if I missed any
It's already too long for my attention span I'm afraid.
Can you buy parts from Digi-Key or Mouser?