segmentation of current output dac

[shriraj19]

hi
i want to design a current output dac having segmented architecture of binary+unary weighted ,i want to know that for N bit dac design what factors decides segmentation and how optimum segmentation can be done wrt. accuracy,speed and area?

 

[kalyanasv]

Hi,

For a N bit DAC you will have 2^N possible values, the segmentation implies you have a current source generator for each of those 2^N bits. Segmentation provides speed but implies creation of for e.g. a resistor network based current source for each bit value. The accuracy should not really be affected by segmentation (ideally). The area does increase with segmentation. Essentially it is a tradeoff between area and speed that you are dealing with depending on your application you have to decide.