Limit Push Button Digi Pot Output Resistance ( Maxim DS1809-10 )

[interrupted]

Hi,

like the Threadtopic already says, i am looking for a way to limit the Output Resistance Range from a Maxim DS1809 IC which supports up to 10k Output Resistance. The Application Notes dont say anything about this, by myself i  was only able to archive it "somehow" with parallel hooked up fix Resistors. Which turned out as an absolut stupid idea which wont work.

Reducing the Output Range from 10 to 5k without adding a non linear behavior is something i am looking for. Maybe i should try 2 of the DS1809 Stacked to half the output.

But, i am pretty sure that its not needed to go that ugly way. Maybe anyone got a hint how to archive this?

Spec Sheet for the IC is https://datasheets.maximintegrated.com/en/ds/DS1809.pdf

Thanks!

Juergen

[danadak]

What is the 1809 controlling, what is its variable R being used in rest
of solution ?

One possibility, convert the pot voltage to a current source with OpAmp.
Again depends on answer to above question.


Regards, Dana.