Machsupport Forum

Third party software and hardware support forums. => PoKeys => Topic started by: Bill_O on March 05, 2009, 01:14:12 PM

Title: potentiometer voltage
Post by: Bill_O on March 05, 2009, 01:14:12 PM

Can the voltage for pots be 5 instead of 3.3?
I want to use a hall effect joystick and they only work with 5.
Bill

Title: Re: potentiometer voltage
Post by: borisz on March 05, 2009, 01:24:50 PM

It can be 5V, but it will measure only up to 3,3V.
Probaly it can be done with simple resistor divider.
What is the resistance of potentiometer?

regards

Boris

Title: Re: potentiometer voltage
Post by: Bill_O on March 05, 2009, 02:25:39 PM

Boris,
So if I use the 5v from the pokeys instead of the 3.3v it will not blow up my pokeys or pc?
Bill

Title: Re: potentiometer voltage
Post by: borisz on March 05, 2009, 03:01:06 PM

It is limited to 5V, but it will measure only up to 3,3V.
If more than 5V e.g. 5,1V will be connected analog inputs will be blown.
For security reason, my opinion is that you shoud limit voltage to 3,3V. Please write more about your application and about your potentiometer and I will suggest you right solution.

regards

Boris

Title: Re: potentiometer voltage
Post by: M250cnc on April 15, 2009, 11:26:40 AM

Hi Borisz

Is it OK to use a separate supply of 3.3v for the pots

I use a PC power supply for my 5 & 12v but they also can supply 3.3v so this seems ideal ?

Thanks

Title: Re: potentiometer voltage
Post by: borisz on April 15, 2009, 11:52:44 AM

It should be OK.

regards

Boris