Optimum Segmentation for High Speed Current Steering Digital-to-Analog Converters

When designing a Current Steering Digital to Analog Converter, a major architectural parameter is the number of bits in the partitioning between thermometer and binary segments. This is called segmentation. The DAC designer has to choose the optimum amount of segmentation taking into account the physical problems associated with the segmentation. Current steering DACs with a low amount of segmentation have the advantage that they are simple. They only need a few current sources and switches. A disadvantage of low segmentation is the possible larger DNL compared to the converters with larger segmentation. Converters with larger segmentation have a lower DNL, but the problems associated with the output conductance, capacitance and synchronization increase and also the area and power that is needed increases.