Re: Why DAC is not monotonic
Well, the reason for that is because your DAC is in binary mode. To reduce the glitches, you have to put the top few bits in the thermometric code. If you are designing a 6 bit DAC, you can put 3 bits in binary and 3 in thermometric.
At the device level, you should take care of your switch sizes. Because of charge feedthrough, there will be glitches due to the charge injection.
Finally, see whether you are using proper clocks. Depending on the architecture, you should see whether you have a overlapping or a non-overlapping clock