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DAC Limitations

The output of a DAC can only assume discrete values. The relationship between the input binary number and the analog output of a perfect DAC is shown in figure 8.3.

Figure 8.3:  Output signals from DACs showing a) the ideal result, and b) a differential nonlinearity or c) non-monotonic behavior, both caused by imperfectly matched resistors.

Common DAC limitations are an anomalous step size between adjacent binary numbers, non-monotonic behaviour, or a zero output.

Doug Gingrich
Tue Jul 13 16:55:15 EDT 1999