That information should be listed in the specifications of your DAQ card manual. Typically -10V is common.
Or are you asking for the smallest increment of voltage change possible? If so that can be calculated by taking the range of output and dividing it by 2 raised to the power of the number of bits on the DAC. For example, if the manual states that the range of the analog output is -10V to +10V, that is a range of 20 volts. Number of bits you stated is 12. So, 20V/(2^12) = 20V/4096 = 4.88mV per increment step. There may be slight offset and gain non-linearities, do not know the model of DAQ card you have.
Hope this helps
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"It’s the questions that drive us.”
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