Digital Potentiometer

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.

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

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 They were originally made by Xicor.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**

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**

ghauri said:

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.

Click to expand...

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