Digital Potentiometer

[ghauri]

We change the resistance in a potentiometer mechanically
I want to design a digital potentiometer(variable Resistor) whcose Resistance can be changed by just using different combination
Let say i have 2 bits then 4 combination so it covers total value of that potensiometer
Is there something like that exist if yes plz tell.

 

[Dr.EM]

You want an DAC followed by the circuit of figure 10 here:

http://www.datasheetcatalog.com/datasheets_pdf/L/M/1/3/LM13700.shtml

If you require it to be used as a volume control, look at figure 4 or 2. Alternatively source a specialised VCA chip such as THAT2180

For the DAC try:



Or alternatively a specialised DAC chip

 

[Papabravo]

There is a product called an EEPot. The output is controlled by a single digital siganl that moves the output either up or down. They were originally made by Xicor.

Top Google hit
**broken link removed**

 

[philba]

assuming you want to control it electronically (vs mechanically via switches), look into digital pots from a number of companies. maxim carries quite a variety - **broken link removed**

 

[em2006]

We change the resistance in a potentiometer mechanically
I want to design a digital potentiometer(variable Resistor) whcose Resistance can be changed by just using different combination
Let say i have 2 bits then 4 combination so it covers total value of that potensiometer Is there something like that exist if yes plz tell.

See my project, using common components (digpot.png)
No need special Ics.