Interferences beteen components

Hi,

in my project i use a pot and a bluetooth controller among other components. If I put the gnd of those two components together the readings of the pot become unstable. As arduino has more than one gnd I put the pot alone and the rest of components together in another pin and this helps. I would like to know what is between both gnd to avoid this noise. How can I isolate the pot?

Thank you very much!

Star-grounding - every sensor gets its own ground-return line indepedent from any other.

That way you don't get cross-talk due to ground currents. Same for the Vcc to the other end of the pot.

You might want to try adding some capacitance between the analog pin and ground for the pot wiper connection, say 10 to 100nF, which will reduce any pick-up.

Hi MarkT,

ground line is independent for the pot assuming gnd pins in arduino are. Not for the vcc. How can I isolate the vcc from one other?

I will try your suggestion of adding capacitance between ground and the analog pin.

Thank you very much MarkT!

Hi,

I added the capacitance (100 uF 6.3v?) for the pot but it didn't help. All components share vcc and gnd except the pot. When I disconnect the ground from the bluetooth chip readings of the analog pin of the pot become stable. Is there any other "filter" i could use to isolate the bluetooth chip?

Thank you,

100uF wont do very much, try a smaller cap like 100nF.

Hi, Can you post a picture of you project so we can see you component layout?

Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?

What is you power supply for your project?

Thanks.. Tom.. :)

Hi,

thanks TobiasD, I'll try that. ASAP I'll provide a schematic of the project.

Regards,