Hi everyone,
basically I'm creating a device to control various automotive dashboards (in the future, more than one at the same time). On newer dashboards most stuff is simple because info is sent by CAN, however on old units many sensors are variable resistors (mainly temperature sensors and tank fuel level sensors).
I need a way to
simulate these sensors and control their value with a microcontroller.
I'm aware of digital potentiometers but there are no pots that can emulate in the resistance I need.
Usually 5 ohms to 200 ohms.Here are some examples of fuel level sensors:
240-33 Ohms - Standard Aftermarket - T-SW-**
10-180 Ohms - VDO gauges - T-VDO-**
0-30 Ohms - GM up to 1964 - T-GME-**
0-90 Ohms - GM 1965 and up - T-GML-**
73-10 Ohms - Early Ford & Mopar - T-ORG-**
Example of the circuit and component I'm emulating:
Usually one side of the component is connected to ground, but not always.
There are 1k digital pots, but at 256 steps and a wiper resistance of 50 ohms is not usable.
Motorized potentiometers could be an option, but I can seem to find 500ohm or 1k ones.
Also it can't be too expensive because I need to create many of these controllers for same project.
Any ideas?