Knowing how voltage dividers work, this probably isn't possible. But, is there a way to run an audio signal back through an R2R arrangement and get 8bit digital signals back out without complex circuitry?

  • \$\begingroup\$ You can turn any DAC into an ADC by adding an analog comparator. \$\endgroup\$
    – Dave Tweed
    Sep 20, 2015 at 11:29
  • \$\begingroup\$ Where would I add it? Elaborate please. \$\endgroup\$
    – nkeck72
    Sep 20, 2015 at 13:55
  • \$\begingroup\$ Connect the DAC to one input, connect your analog voltage to the other, and connect the output to your logic. The logic (e.g., firmware running on a microcontroller) then runs an algorithm such as successive approximation to determine what the analog voltage is. \$\endgroup\$
    – Dave Tweed
    Sep 20, 2015 at 19:32

1 Answer 1


I think you're looking for a Flash ADC:


You can't use the same arrangement though. You need a lot more resistors.

  • \$\begingroup\$ Makes sense. I'm guessing there isn't a way to do it without some form of an IC? \$\endgroup\$
    – nkeck72
    Sep 20, 2015 at 2:36
  • \$\begingroup\$ You could build the comparators out of transistors, but that sounds kinda painful. ICs make things easy! \$\endgroup\$
    – Daniel
    Sep 20, 2015 at 2:39
  • \$\begingroup\$ Im for the ICs most of the time but a 6502 and the VIA plus some other bits and doodads and you suddenly find yourself running out of breadboard space. This is the main reason I chose an R2R DAC. I wonder if maybe instead of 255 comparators (just for 8 bits- \$\endgroup\$
    – nkeck72
    Sep 20, 2015 at 2:43
  • \$\begingroup\$ I use a different style? Is there another that may save space? \$\endgroup\$
    – nkeck72
    Sep 20, 2015 at 2:44
  • \$\begingroup\$ Just find an off the shelf SPI ADC or something... ? \$\endgroup\$
    – Daniel
    Sep 20, 2015 at 2:47

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.