Digital Potentiometer Issues

Discussion in 'General Electronics Chat' started by stoopkid, Sep 29, 2011.

  1. stoopkid

    Thread Starter Member

    Mar 3, 2011
    I got an AD5206BN10 six channel digital potentiometer to control the five pots on a 9v guitar pedal circuit, controlled by an arduino. The whole thing was messing up my arduino and I found out that this IC doesn't take more than 5v in the actual pot circuits.

    My problem is that they DO have digital pots that can handle 9v but they are single channel and the arduino only does two of those at a time. I am trying to find something that fits my needs, 6 channel, >9v, but I can't find anything.

    BTW, this is the pedal schematic and this is the arduino tutorial i used if that matters.

    I really need a push in the right direction at this point, I would really appreciate any help. Thanks.
  2. ErnieM

    AAC Fanatic!

    Apr 24, 2011
    Do you have any extra I/O pins? A SPI bus can run multiple devices as long as each has their own chip select: you select one device and talk to it over one common SPI channel.

    If you're short on I/O, use the other Arduino SPI channel to run an I/O expander.

    Wikipedia on SPI Bus

  3. CraigHB


    Aug 12, 2011
    I ran into a similar problem with pot voltages on a project I was working on. All of the digital pots I've looked at are limited in the voltage they can accept on the resistive pins by Vdd (supply voltage). I was able to get the pot to accept higher voltages by running a higher Vdd, but then I got that Vdd on the pot's SDO pin (SPI data ouput) which was too high for the MCU.

    I probably could have just done something to drop some voltage on SDO but it all started getting too convoluted. I ended up redesigning the circuit so the resistive part of the pot was on the low side. It's a bit tricky working out a digital pot to control something at voltages higher than bus and supply voltages.