WM5621L
Functional Description (continued)
For a DAC, linearity is measured between ZERO input code
( all inputs 0 ) and full scale code ( all inputs 1 ) after offset
and full scale are adjusted out or accounted for in some
way. However, single supply operation does not allow for
adjustment when the offset is negative due to the break-
point in the transfer function. So the linearity in the unipolar
mode is measured between full scale code and the lowest
code which produces a positive output voltage. The code
is calculated from the maximum specification for the
negative offset.
Figure 5: Effect of negative offset (single supply)
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