Sensor 12V Stability

[CTX-SLPR]

How stable does the 12V supply to sensors and how locked down to 12V does it need to be? I would think that it would need to be regulated to 12V to keep the resistance based 0-5V output consistent but that's me thinking not knowing.

Thanks,

[Matt Cramer]

For analog sensors, the stability is critical, although 12V analog sensors are pretty rare (and several of them use an internal regulator to stabilize things). For an on/off sensor (Hall effect, for example), they're either on or off, so the exact voltage is usually a non-issue. If you do run into issues with a Hall effect sensor, you could put a capacitor on power feed wire.

[Barry Donovan]

start with a damn good alternator.

not easy to narrow down, but they re going for 20+ years now, as very good.
internal fan is a simple indicator of going modern.

[CTX-SLPR]

This is an odd one I'm asking for. It's a Bosch K-Jet potentiometer on the side of the mechanical MAF that measures the air flapper position. The Audi documentation I've seen shows a 12V input and a ground with a 0-5V output. It sounds like it is an internally regulated source to the sensor to keep it stable. I'll have to try out my Merc (same sensor) unit with a 9V and 12V sources and see if i get the same range of voltage off of the sensor.

Mainly looking at logging everything possible though a 48 channel MUX board on an Arduino for my LSR destroker.

[ka67_72]

You could use an inverter to power a regulated power supply. A DC to DC converter might work but may cause too much ripple.