Calibration in ADC and DAC

Discussion in 'General Electronics Chat' started by Surendar, Jan 3, 2006.

  1. Surendar

    Thread Starter Member

    Sep 12, 2005
    I need to know pricniple of calibration in ADC and DAC ckts and how it's done.

    Pls attach some figures if necessary.


  2. beenthere

    Retired Moderator

    Apr 20, 2004

    If you have a converter from the supplier, then the data sheet will give you the figures.

    If you want to check on one, you will need a stable voltage source and a bench meter with better spec's than the device under test. For the DAC, you have it convert some digital value, and use the meter to verify the accuracy of the output voltage (or current).

    The ADC is a bit more complicated, but the basic technique is to apply a known voltage and check that the digital value matches it. Unless your ADC is homemade, you usually only need to check 0 volts and full scale. A slow ramp voltage can give you an indication that the ADC is catching all the values.

    Generally, these things work per spec's, or not at all. In the bad old days, I kept up a multiple-channel DAC - ADC that ran data between the digital computers and the analog computers. If all worked well, it need 20 hours to go through and verify all functions - you just put in 4 hours a day and hoped for the best.