Hi guys,
i need to separate the GNDs of my Arduino Due. Is there any easy solution ? Trying to realize a couple of sensors, but i think they are influencing each other as they all run with the same GND.
kind regards !
The Arduino Due has analog grounds connected to the digital grounds and to power supply grounds.
http://arduino.cc/en/Main/arduinoBoardDue
The best thing you can do, is the to use the Arduino Due as the central unit where all grounds are connected.
Sensors should be connected with a bundle of wires from the Arduino Due to the sensor, inclusive the ground wire. So the ground signal is connected to the Arduino Due, and not half-way to an other ground.
You can use opto-couplers to seperate grounds.
In most cases it is not a problem, but I read that aquarium ph-probes can be a real trouble.
Thanks a lot !
If there are more ideas feel free to post !!!
Does anybody has experience with floating ground ?
Iam totally interessted in more brainstorming 
What problem do you actually think you are having ?
What do you mean by "separate grounds" and "floating grounds"?
I have a couple of sensors which should work all separate.
But if i start a measurement all sensors induce the signal to the others so i can not distinguish the signals anymore.
Therefore i tried a lot of arrangment of the sensors and circuits to separate them... but still i have the coupling effect.
In the end the circuits were totally separated from each other .... i installed each sensor on a separate arduino board.... but still no solution in sight. As a newby, I concluded that the GND pins are the only linkage between the sensors (I even run on sensor with a battery...) . Maybe this is a wrong approach... but otherwise i run out of ideas!?
btw.: Floating Ground
What sort of sensors ? How are they connected ? What do you think you mean, when you say that one sensor is influencing the others ?
I like to build a theremin, similar to this:
http://interface.khm.de/index.php/lab/experiments/theremin-as-a-capacitive-sensing-device/
I mainly try to manage the capacitive sensors...
As I would like to control the volume and some other accustic effects, i need to build a couple of them. The circuits generate a frequency which is aligned with a specific effect(volume, tune, gain...). Frequencies between 4-4,5Mhz result in note A... For example. Until now i have managed to handle each single effect. Now my problem is to use them in parallel ... like start with the note A (4Mhz) ... with low volume (other sensor 1Mhz).
My circuit is a constrcuted like it is shown in the link above here. The Grounds are all connected together and also the 3,3Volt supply voltage. The signal is wired from IC leg 8 to the desired timer pin on the Due. (For the first counter chanel 22, 31 , A5, A3 )
What I mean with influencing: if i move my hand infront of one sensor the signal raises (4MHz goes to 6MHz). But the signal raises for the other sensors as well .... thats unintended. (By the way the sensors are spatially divided around 1,5-2m)
Your problem is very likely the connections between the "sensors" and the Arduino. "Ground" may not actually be ground when radio frequency currents are involved. The author of that web page comments:
It must be noticed that also that all metal parts like usb cable, connected speaker, even the connected computer are loaded by the RF signal and tend to be “hot” so that they work as antenna as well.
If you are not using shielded cable to connect the sensors to the Arduino, you certainly should try it. You will probably also have to put the Arduino into a sealed metal box that is itself grounded. However, this may not work for the above reasons.
Hi there,
solved the problem by using DCDC converter for each sensor.
I am using a 5 volt dc main adapter and split the voltage supply by the galvanic separated converter !