Sender voltage and calibration

[denpo]

Ok, I'm making progress in my digital gauge setup and now I'm about do design the sensing part, reading from senders (oil pressure, water temp, fuel level)
In the stock form the senders are fed 12v. I was wondering if those could be fed by the same regulated 5v I'm powering the circuit with.
That would make my circuit much simpler.
On the paper it look feasible, the sender are just variable resistor, but better safe than sorry...

Also,
since for my current oil and water senders are mechanical, I'll need to buy electric ones, any recommandation? I'm looking for senders that have well documented reponse curve.

 

[69427]

Do your gauges have the A/D converters built in, or are they on a separate board?

 

[denpo]

Do your gauges have the A/D converters built in, or are they on a separate board?

The digital gauge system is actually
-a input board, that make sure the signal from sensor is armless to the converter
-a microcontrolleur that contain the A/D converters plus all the logic to display the data
-a bunch of Oled screen, 6 for now that display the result.

For connecting the A/D to the sender signal, I'm getting inspiration from the MegaSquirt design.
In their case it's at simple resistor divider setup.
http://www.bgsoflex.com/v22/megasquirt_ShemV2.2.pdf (see page 2)

Because they feed their sensor with the same regulated and protected 5v they feed the microcontrolleur with, they only need extensive transient protection at one single location (the main 5v feed).
I was just wondering if I could do the same.
I got the feeling I can, but maybe you know this geek saying :
"In theory, practice and theory are the same. In practice, they aren't"